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Author Yagmurcukardes, M. url  doi
openurl 
  Title Stable anisotropic single-layer of ReTe₂ : a first principles prediction Type A1 Journal article
  Year 2020 Publication Turkish Journal of Physics Abbreviated Journal  
  Volume 44 Issue 5 Pages 450-457  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In order to investigate the structural, vibrational, electronic, and mechanical features of single-layer ReTe2 first-principles calculations are performed. Dynamical stability analyses reveal that single-layer ReTe2 crystallize in a distorted phase while its 1H and 1T phases are dynamically unstable. Raman spectrum calculations show that single-layer distorted phase of ReTe2 exhibits 18 Raman peaks similar to those of ReS2 and ReSe2. Electronically, single-layer ReTe2 is shown to be an indirect gap semiconductor with a suitable band gap for optoelectronic applications. In addition, it is found that the formation of Re-units in the crystal induces anisotropic mechanical parameters. The in-plane stiffness and Poisson ratio are shown to be significantly dependent on the lattice orientation. Our findings indicate that single-layer form of ReTe2 can only crystallize in a dynamically stable distorted phase formed by the Re-units. Single-layer of distorted ReTe2 can be a potential in-plane anisotropic material for various nanotechnology applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000585330600004 Publication Date 2020-09-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1300-0101 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) Times cited Open Access  
  Notes ; Computational resources were provided by the Scientific and Technological Research Council of Turkey (TUBITAK) Turkish Academic Network and Information Center (ULAKBIM), High Performance and Grid Computing Center (TR-Grid e-Infrastructure) and by Flemish Supercomputer Center (VSC). This work was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:174296 Serial 6698  
Permanent link to this record
 

 
Author Duran, T.A.; Yayak, Y.O.; Aydin, H.; Peeters, F.M.; Yagmurcukardes, M. pdf  doi
openurl 
  Title A perspective on the state-of-the-art functionalized 2D materials Type A1 Journal article
  Year 2023 Publication Journal of applied physics Abbreviated Journal  
  Volume 134 Issue 12 Pages 120901-120929  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional (2D) ultra-thin materials are more crucial than their bulk counterparts for the covalent functionalization of their surface owing to atomic thinness, large surface-to-volume ratio, and high reactivity of surface atoms having unoccupied orbitals. Since the surface of a 2D material is composed of atoms having unoccupied orbitals, covalent functionalization enables one to improve or precisely modify the properties of the ultra-thin materials. Chemical functionalization of 2D materials not only modifies their intrinsic properties but also makes them adapted for nanotechnology applications. Such engineered materials have been used in many different applications with their improved properties. In the present Perspective, we begin with a brief history of functionalization followed by the introduction of functionalized 2D materials. Our Perspective is composed of the following sections: the applications areas of 2D graphene and graphene oxide crystals, transition metal dichalcogenides, and in-plane anisotropic black phosphorus, all of which have been widely used in different nanotechnology applications. Finally, our Perspectives on the future directions of applications of functionalized 2D materials are given. The present Perspective sheds light on the current progress in nanotechnological applications of engineered 2D materials through surface functionalization.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001087770500008 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record  
  Impact Factor (up) Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:201281 Serial 9000  
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Author Hassani, N.; Yagmurcukardes, M.; Peeters, F.M.; Neek-Amal, M. pdf  doi
openurl 
  Title Chlorinated phosphorene for energy application Type A1 Journal article
  Year 2024 Publication Computational materials science Abbreviated Journal  
  Volume 231 Issue Pages 112625-112628  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The influence of decoration with impurities and the composition dependent band gap in 2D materials has been the subject of debate for a long time. Here, by using Density Functional Theory (DFT) calculations, we systematically disclose physical properties of chlorinated phosphorene having the stoichiometry of PmCln. By analyzing the adsorption energy, charge density, migration energy barrier, structural, vibrational, and electronic properties of chlorinated phosphorene, we found that (I) the Cl-P bonds are strong with binding energy Eb =-1.61 eV, decreases with increasing n. (II) Cl atoms on phosphorene have anionic feature, (III) the migration path of Cl on phosphorene is anisotropic with an energy barrier of 0.38 eV, (IV) the phonon band dispersion reveal that chlorinated phosphorenes are stable when r <= 0.25 where r = m/n, (V) chlorinated phosphorenes is found to be a photonic crystal in the frequency range of 280 cm-1 to 325 cm-1, (VI) electronic band structure of chlorinated phosphorenes exhibits quasi-flat bands emerging around the Fermi level with widths in the range of 22 meV to 580 meV, and (VII) Cl adsorption causes a semiconducting to metallic/semi-metallic transition which makes it suitable for application as an electroactive material. To elucidate this application, we investigated the change in binding energy (Eb), specific capacity, and open-circuit voltage as a function of the density of adsorbed Cl. The theoretical storage capacity of the chlorinated phosphorene is found to be 168.19 mA h g-1with a large average voltage (similar to 2.08 V) which is ideal number as a cathode in chloride-ion batteries.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001110003400001 Publication Date 2023-11-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-0256 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:202125 Serial 9008  
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Author Wahab, O.J.; Daviddi, E.; Xin, B.; Sun, P.Z.; Griffin, E.; Colburn, A.W.; Barry, D.; Yagmurcukardes, M.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M.; Unwin, P.R. url  doi
openurl 
  Title Proton transport through nanoscale corrugations in two-dimensional crystals Type A1 Journal article
  Year 2023 Publication Nature Abbreviated Journal  
  Volume 620 Issue 7975 Pages 1-17  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Defect-free graphene is impermeable to all atoms(1-5) and ions(6,7) under ambient conditions. Experiments that can resolve gas flows of a few atoms per hour through micrometre-sized membranes found that monocrystalline graphene is completely impermeable to helium, the smallest atom(2,5). Such membranes were also shown to be impermeable to all ions, including the smallest one, lithium(6,7). By contrast, graphene was reported to be highly permeable to protons, nuclei of hydrogen atoms(8,9). There is no consensus, however, either on the mechanism behind the unexpectedly high proton permeability(10-14) or even on whether it requires defects in graphene's crystal lattice(6,8,15-17). Here, using high-resolution scanning electrochemical cell microscopy, we show that, although proton permeation through mechanically exfoliated monolayers of graphene and hexagonal boron nitride cannot be attributed to any structural defects, nanoscale non-flatness of two-dimensional membranes greatly facilitates proton transport. The spatial distribution of proton currents visualized by scanning electrochemical cell microscopy reveals marked inhomogeneities that are strongly correlated with nanoscale wrinkles and other features where strain is accumulated. Our results highlight nanoscale morphology as an important parameter enabling proton transport through two-dimensional crystals, mostly considered and modelled as flat, and indicate that strain and curvature can be used as additional degrees of freedom to control the proton permeability of two-dimensional materials. A study using high-resolution scanning electrochemical cell microscopy attributes proton permeation through defect-free graphene and hexagonal boron nitride to transport across areas of the structure that are under strain.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001153630400007 Publication Date 2023-08-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836; 1476-4687 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:203827 Serial 9078  
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Author Bafekry, A.; Shahrokhi, M.; Yagmurcukardes, M.; Gogova, D.; Ghergherehchi, M.; Akgenc, B.; Feghhi, S.A.H. pdf  url
doi  openurl
  Title Surface functionalization of the honeycomb structure of zinc antimonide (ZnSb) monolayer : a first-principles study Type A1 Journal article
  Year 2021 Publication Surface Science Abbreviated Journal Surf Sci  
  Volume 707 Issue Pages 121796  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Structural, electronic, optic and vibrational properties of Zinc antimonide (ZnSb) monolayers and their func-tionalized (semi-fluorinated and fully chlorinated) structures are investigated by means of the first-principles calculations. The phonon dispersion curves reveal the presence of imaginary frequencies and thus confirm the dynamical instability of ZnSb monolayer. The calculated electronic band structure corroborates the metallic character with fully-relativistic calculations. Moreover, we analyze the surface functionalization effect on the structural, vibrational, and electronic properties of the pristine ZnSb monolayer. The semi-fluorinated and fully-chlorinated ZnSb monolayers are shown to be dynamically stable in contrast to the ZnSb monolayer. At the same time, semi-fluorination and fully-chlorination of ZnSb monolayer could effectively modulate the metallic elec-tronic properties of pristine ZnSb. In addition, a magnetic metal to a nonmagnetic semiconductor transition with a band gap of 1 eV is achieved via fluorination, whereas a transition to a semiconducting state with 1.4 eV band gap is found via chlorination of the ZnSb monolayer. According to the optical properties analysis, the first ab-sorption peaks of the fluorinated-and chlorinated-ZnSb monolayers along the in-plane polarization are placed in the infrared range of spectrum, while they are in the middle ultraviolet for the out-of-plane polarization. Interestingly, the optically anisotropic behavior of these novel monolayers along the in-plane polarizations is highly desirable for design of polarization-sensitive photodetectors. The results of the calculations clearly proved that the tunable electronic properties of the ZnSb monolayer can be realized by chemical functionalization for application in the next generation nanoelectronic devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000626633500001 Publication Date 2020-12-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0039-6028 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 2.062 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 2.062  
  Call Number UA @ admin @ c:irua:177623 Serial 7026  
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Author Yagmurcukardes, M.; Sahin, H.; Kang, J.; Torun, E.; Peeters, F.M.; Senger, R.T. doi  openurl
  Title Pentagonal monolayer crystals of carbon, boron nitride, and silver azide Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 118 Issue 118 Pages 104303  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this study, we present a theoretical investigation of structural, electronic, and mechanical properties of pentagonal monolayers of carbon (p-graphene), boron nitride (p-B2N4 and p-B4N2), and silver azide (p-AgN3) by performing state-of-the-art first principles calculations. Our total energy calculations suggest feasible formation of monolayer crystal structures composed entirely of pentagons. In addition, electronic band dispersion calculations indicate that while p-graphene and p-AgN3 are semiconductors with indirect bandgaps, p-BN structures display metallic behavior. We also investigate the mechanical properties (in-plane stiffness and the Poisson's ratio) of four different pentagonal structures under uniaxial strain. p-graphene is found to have the highest stiffness value and the corresponding Poisson's ratio is found to be negative. Similarly, p-B2N4 and p-B4N2 have negative Poisson's ratio values. On the other hand, the p-AgN3 has a large and positive Poisson's ratio. In dynamical stability tests based on calculated phonon spectra of these pentagonal monolayers, we find that only p-graphene and p-B2N4 are stable, but p-AgN3 and p-B4N2 are vulnerable against vibrational excitations.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000361636900028 Publication Date 2015-09-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 2.068 Times cited 79 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge the support from TUBITAK through Project No. 114F397. ; Approved Most recent IF: 2.068; 2015 IF: 2.183  
  Call Number UA @ lucian @ c:irua:128415 Serial 4223  
Permanent link to this record
 

 
Author Akgenc, B.; Sarikurt, S.; Yagmurcukardes, M.; Ersan, F. pdf  url
doi  openurl
  Title Aluminum and lithium sulfur batteries : a review of recent progress and future directions Type A1 Journal article
  Year 2021 Publication Journal Of Physics-Condensed Matter Abbreviated Journal J Phys-Condens Mat  
  Volume 33 Issue 25 Pages 253002  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Advanced materials with various micro-/nanostructures have attracted plenty of attention for decades in energy storage devices such as rechargeable batteries (ion- or sulfur based batteries) and supercapacitors. To improve the electrochemical performance of batteries, it is uttermost important to develop advanced electrode materials. Moreover, the cathode material is also important that it restricts the efficiency and practical application of aluminum-ion batteries. Among the potential cathode materials, sulfur has become an important candidate material for aluminum-ion batteries cause of its considerable specific capacity. Two-dimensional materials are currently potential candidates as electrodes from lab-scale experiments to possible pragmatic theoretical studies. In this review, the fundamental principles, historical progress, latest developments, and major problems in Li-S and Al-S batteries are reviewed. Finally, future directions in terms of the experimental and theoretical applications have prospected.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000655281200001 Publication Date 2021-04-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 2.649 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 2.649  
  Call Number UA @ admin @ c:irua:179034 Serial 6971  
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Author Ozcan, M.; Ozen, S.; Yagmurcukardes, M.; Sahin, H. pdf  doi
openurl 
  Title Structural, electronic and vibrational properties of ultra-thin octahedrally coordinated structure of EuO2 Type A1 Journal article
  Year 2020 Publication Journal Of Magnetism And Magnetic Materials Abbreviated Journal J Magn Magn Mater  
  Volume 493 Issue 493 Pages 165668  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Novel stable ultra-thin phases of europium oxide are investigated by means of state-of-the-art first principles calculations. Total energy calculations show that single layers of EuO2 and Eu(OH)(2) can be stabilized in an octahedrally coordinated (1T) atomic structure. However, phonon calculations reveal that although both structures are energetically feasible, only the 1T-EuO2 phase has dynamical stability. The phonon spectrum of 1T-EuO2 displays three Raman active modes; a non-degenerate out-of-plane A(1g) mode at 353.5 cm(-1) and two doubly-degenerate in-plane E-g modes at 304.3 cm(-1). Furthermore, magnetic ground state and electronic band dispersion calculations show that the single layer EuO2 is a metal with net magnetic moment of 5(mu B) per unitcell resulting in a half-metallic ferrimagnetic behavior. Moreover, robustness of the half-metallic ferrimagnetic characteristics of EuO2 is confirmed by the application of electric field and charging. Single layer 1T-EuO2, with its stable ultra-thin structure and half-metallic ferrimagnetic feature, is a promising novel material for nanoscale electronic and spintronic applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000486397800003 Publication Date 2019-08-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-8853 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 2.7 Times cited 1 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS acknowledges financial support from the TUBITAK under the project number 117F095. MY is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship. ; Approved Most recent IF: 2.7; 2020 IF: 2.63  
  Call Number UA @ admin @ c:irua:162755 Serial 6323  
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Author Kahraman, Z.; Yagmurcukardes, M.; Sahin, H. pdf  doi
openurl 
  Title Functionalization of single-layer TaS₂ and formation of ultrathin Janus structures Type A1 Journal article
  Year 2020 Publication Journal Of Materials Research Abbreviated Journal J Mater Res  
  Volume 35 Issue 11 Pages 1397-1406  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Ab initio calculations are performed to investigate the structural, vibrational, electronic, and piezoelectric properties of functionalized single layers of TaS2. We find that single-layer TaS2 is a suitable host material for functionalization via fluorination and hydrogenation. The one-side fluorinated (FTaS2) and hydrogenated (HTaS2) single layers display indirect gap semiconducting behavior in contrast to bare metallic TaS2. On the other hand, it is shown that as both surfaces of TaS2 are saturated anti-symmetrically, the formed Janus structure is a dynamically stable metallic single layer. In addition, it is revealed that out-of-plane piezoelectricity is created in all anti-symmetric structures. Furthermore, the Janus-type single-layer has the highest specific heat capacity to which longitudinal and transverse acoustical phonon modes have contribution at low temperatures. Our findings indicate that single-layer TaS2 is suitable for functionalization via H and F atoms that the formed, anti-symmetric structures display distinctive electronic, vibrational, and piezoelectric properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000540764300005 Publication Date 2020-04-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0884-2914 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 2.7 Times cited 1 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. Acknowledges financial support from the TUBITAK under the project number 117F095. H.S. acknowledges support from Turkish Academy of Sciences under the GEBIP program. This work is supported by the Flemish Science Foundation (FWO-Vl) by a post-doctoral fellowship (M.Y.). ; Approved Most recent IF: 2.7; 2020 IF: 1.673  
  Call Number UA @ admin @ c:irua:170185 Serial 6525  
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Author Yorulmaz, U.; Šabani, D.; Yagmurcukardes, M.; Sevik, C.; Milošević, M.V. pdf  doi
openurl 
  Title High-throughput analysis of tetragonal transition metal Xenes Type A1 Journal article
  Year 2022 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 24 Issue 48 Pages 29406-29412  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We report a high-throughput first-principles characterization of the structural, mechanical, electronic, and vibrational properties of tetragonal single-layer transition metal Xenes (t-TMXs). Our calculations revealed 22 dynamically, mechanically and chemically stable structures among the 96 possible free-standing layers present in the t-TMX family. As a fingerprint for their structural identification, we identified four characteristic Raman active phonon modes, namely three in-plane and one out-of-plane optical branches, with various intensities and frequencies depending on the material in question. Spin-polarized electronic calculations demonstrated that anti-ferromagnetic (AFM) metals, ferromagnetic (FM) metals, AFM semiconductors, and non-magnetic semiconductor materials exist within this family, evidencing the potential of t-TMXs for further use in multifunctional heterostructures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000892446100001 Publication Date 2022-11-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.3 Times cited 1 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.3  
  Call Number UA @ admin @ c:irua:192762 Serial 7310  
Permanent link to this record
 

 
Author Bafekry, A.; Yagmurcukardes, M.; Shahrokhi, M.; Ghergherehchi, M.; Kim, D.; Mortazavi, B. pdf  doi
openurl 
  Title Electro-optical and mechanical properties of Zinc antimonide (ZnSb) monolayer and bilayer : a first-principles study Type A1 Journal article
  Year 2021 Publication Applied Surface Science Abbreviated Journal Appl Surf Sci  
  Volume 540 Issue 1 Pages 148289  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Latest synthesis of ZnSb monolayer, encouraged us to conduct density functional theory (DFT) simulations in order to study the structural, magnetic, electronic/optical and mechanical features of the sp2-hybridized honeycomb ZnSb monolayer (ML-ZnSb) and bilayer (BL-ZnSb). Our structural optimizations reveal that ML-ZnSb is an anisotropic hexagonal structure while BL-ZnSb is composed of shifted ZnSb layers which are covalently binded. ML-ZnSb is found to be a ferromagnetic metal, in contrast BL-ZnSb has a non-magnetic indirect band gap semiconducting ground state. For the in-plane polarization, first absorption peak of ML-ZnSb and BL-ZnSb confirm the absorbance of the light within the infrared domain wand visible range, respectively. Moreover, our results reveal that the layer-layer chemical bonding in BL-ZnSb significantly enhances the mechanical response of ML-ZnSb whose in-plane stiness is the smallest among all 2D materials (2DM). Notably, the strong in-plane anisotropy of ML-ZnSb in its stiness reduces in BL-ZnSb.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000599883200005 Publication Date 2020-11-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0169-4332 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.387 Times cited 1 Open Access Not_Open_Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). Computational resources were provided by the Flemish Supercomputer Center (VSC). M.Y. is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship. B.M. and X. Z. appreciate the funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germanys Excellence Strategy within the Cluster of Excellence PhoenixD (EXC 2122, Project ID 390833453). ; Approved Most recent IF: 3.387  
  Call Number UA @ admin @ c:irua:174956 Serial 6688  
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Author Kahraman, Z.; Baskurt, M.; Yagmurcukardes, M.; Chaves, A.; Sahin, H. pdf  doi
openurl 
  Title Stable Janus TaSe₂ single-layers via surface functionalization Type A1 Journal article
  Year 2021 Publication Applied Surface Science Abbreviated Journal Appl Surf Sci  
  Volume 538 Issue Pages 148064  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract First-principles calculations are performed in order to investigate the formation of Janus structures of single layer TaSe2. The structural optimizations and phonon band dispersions reveal that the formation and stability of hydrogenated (HTaSe2), fluorinated (FTaSe2), and the one-side hydrogenated and one-side fluorinated (Janus-HTaSe2F) single-layers are feasible in terms of their phonon band dispersions. It is shown that bare metallic single-layer TaSe2 can be turned into a semiconductor as only one of its surface is functionalized while it remains as a metal via its two surfaces functionalization. In addition, the semiconducting nature of single-layers HTaSe2 and FTaSe2 and the metallic behavior of Janus TaSe2 are found to be robust under applied uniaxal strains. Further analysis on piezoelectric properties of the predicted single-layers reveal the enhanced in-plane and out of-plane piezoelectricity via formed Janus-HTaSe2F. Our study indicates that single-layer TaSe2 is a suitable host material for surface functionalization via fluorination and hydrogenation which exhibit distinctive electronic and vibrational properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000595860900001 Publication Date 2020-10-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0169-4332 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.387 Times cited Open Access Not_Open_Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid eInfrastructure). HS acknowledges support from Turkiye Bilimler Akademisi -Turkish Academy of Sciences under the GEBIP program. This work was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: 3.387  
  Call Number UA @ admin @ c:irua:174964 Serial 6699  
Permanent link to this record
 

 
Author Bafekry, A.; Yagmurcukardes, M.; Akgenc, B.; Ghergherehchi, M.; Nguyen, C. doi  openurl
  Title Van der Waals heterostructures of MoS₂ and Janus MoSSe monolayers on graphitic boron-carbon-nitride (BC₃, C₃N, C₃N₄ and C₄N₃) nanosheets: a first-principles study Type A1 Journal article
  Year 2020 Publication Journal Of Physics D-Applied Physics Abbreviated Journal J Phys D Appl Phys  
  Volume Issue Pages 1-10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this work, we extensively investigate the structural and electronic properties of van der Waals heterostructures (HTs) constructed by MoS${2}$/$BC3$, MoS${2}$/$C3N$, MoS${2}$/$C3N4$, MoS${2}$/$C4N3$ and those using Janus MoSSe instead of MoS$2$ by performing density functional theory calculations. The electronic band structure calculations and the corresponding partial density of states reveal that the significant changes are driven by quite strong layer-layer interaction between the constitutive layers. Our results show that although all monolayers are semiconductors as free-standing layers, the MoS${2}$/$C3N$ and MoS${2}$/$C4N3$ bilayer HTs display metallic behavior as a consequence of transfer of charge carriers between two constituent layers. In addition, it is found that in MoSSe/$C3N$ bilayer HT, the degree of metallicity is affected by the interface chalcogen atom type when Se atoms are facing to $C3N$ layer, the overlap of the bands around the Fermi level is smaller. Moreover, the half-metallic magnetic $C4N3$ is shown to form magnetic half-metallic trilayer HT with MoS$2$ independent of the stacking sequence, i.e. whether it is sandwiched or two $C4N3$ layer encapsulate MoS$2$ layer. We further analyze the trilayer HTs in which MoS$2$ is encapsulated by two different monolayers and it is revealed that at least with one magnetic monolayer, it is possible to construct a magnetic trilayer. While the trilayer of $C4N3$/MoS${2}$/$BC3$ and $C4N3$/MoS${2}$/$C3N4$ exhibit half-metallic characteristics, $C4N3$/MoS${_2}$/$C3$N possesses a magnetic metallic ground state. Overall, our results reveal that holly structures of BCN crystals are suitable for heterostructure formation even over van der Waals type interaction which significantly changes electronic nature of the constituent layers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000543344800001 Publication Date 2020-04-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.4 Times cited Open Access  
  Notes Approved Most recent IF: 3.4; 2020 IF: 2.588  
  Call Number UA @ admin @ c:irua:169754 Serial 6651  
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Author Bafekry, A.; Stampfl, C.; Faraji, M.; Yagmurcukardes, M.; Fadlallah, M.M.; Jappor, H.R.; Ghergherehchi, M.; Feghhi, S.A.H. doi  openurl
  Title A Dirac-semimetal two-dimensional BeN4 : thickness-dependent electronic and optical properties Type A1 Journal article
  Year 2021 Publication Applied Physics Letters Abbreviated Journal Appl Phys Lett  
  Volume 118 Issue 20 Pages 203103  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by the recent experimental realization of a two-dimensional (2D) BeN4 monolayer, in this study we investigate the structural, dynamical, electronic, and optical properties of a monolayer and few-layer BeN4 using first-principles calculations. The calculated phonon band dispersion reveals the dynamical stability of a free-standing BeN4 layer, while the cohesive energy indicates the energetic feasibility of the material. Electronic band dispersions show that monolayer BeN4 is a semi-metal whose conduction and valence bands touch each other at the Sigma point. Our results reveal that increasing the layer number from single to six-layers tunes the electronic nature of BeN4. While monolayer and bilayer structures display a semi-metallic behavior, structures thicker than that of three-layers exhibit a metallic nature. Moreover, the optical parameters calculated for monolayer and bilayer structures reveal that the bilayer can absorb visible light in the ultraviolet and visible regions better than the monolayer structure. Our study investigates the electronic properties of Dirac-semimetal BeN4 that can be an important candidate for applications in nanoelectronic and optoelectronic. Published under an exclusive license by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000691329900002 Publication Date 2021-05-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.411 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.411  
  Call Number UA @ admin @ c:irua:181725 Serial 6980  
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Author Kiymaz, D.; Yagmurcukardes, M.; Tomak, A.; Sahin, H.; Senger, R.T.; Peeters, F.M.; Zareie, H.M.; Zafer, C. doi  openurl
  Title Controlled growth mechanism of poly (3-hexylthiophene) nanowires Type A1 Journal article
  Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology  
  Volume 27 Issue 27 Pages 455604  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Synthesis of 1D-polymer nanowires by a self-assembly method using marginal solvents is an attractive technique. While the formation mechanism is poorly understood, this method is essential in order to control the growth of nanowires. Here we visualized the time-dependent assembly of poly (3-hexyl-thiophene-2,5-diyl) (P3HT) nanowires by atomic force microscopy and scanning tunneling microscopy. The assembly of P3HT nanowires was carried out at room temperature by mixing cyclohexanone (CHN), as a poor solvent, with polymer solution in 1,2-dichlorobenzene (DCB). Both pi-pi stacking and planarization, obtained at the mix volume ratio of P3HT (in DCB):CHN (10:7), were considered during the investigation. We find that the length of nanowires was determined by the ordering of polymers in the polymer repetition direction. Additionally, our density functional theory calculations revealed that the presence of DCB and CHN molecules that stabilize the structural distortions due to tail group of polymers was essential for the core-wire formation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000386132600003 Publication Date 2016-10-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.44 Times cited 24 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, the High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules Foundation. HS is supported by a FWO Pegasus-Long Marie Curie Fellowship. HS and RTS acknowledge support from TUBITAK through Project No. 114F397. Also, DA is supported by the Scientific Research Project Fund of Ege University (Project Nr: 12GEE011). ; Approved Most recent IF: 3.44  
  Call Number UA @ lucian @ c:irua:138159 Serial 4350  
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Author Li, L.L.; Bacaksiz, C.; Nakhaee, M.; Pentcheva, R.; Peeters, F.M.; Yagmurcukardes, M. url  doi
openurl 
  Title Single-layer Janus black arsenic-phosphorus (b-AsP): optical dichroism, anisotropic vibrational, thermal, and elastic properties Type A1 Journal article
  Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 101 Issue 13 Pages 134102-134109  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By using density functional theory (DFT) calculations, we predict a puckered, dynamically stable Janus single-layer black arsenic-phosphorus (b-AsP), which is composed of two different atomic sublayers, arsenic and phosphorus atoms. The calculated phonon spectrum reveals that Janus single-layer b-AsP is dynamically stable with either pure or coupled optical phonon branches arising from As and P atoms. The calculated Raman spectrum indicates that due to the relatively strong P-P bonds, As atoms have no contribution to the highfrequency optical vibrations. In addition, the orientation-dependent isovolume heat capacity reveals anisotropic contributions of LA and TA phonon branches to the low-temperature thermal properties. Unlike pristine single layers of b-As and b-P, Janus single-layer b-AsP exhibits additional out-of-plane asymmetry which leads to important consequences for its electronic, optical, and elastic properties. In contrast to single-layer b-As, Janus single-layer b-AsP is found to possess a direct band gap dominated by the P atoms. Moreover, real and imaginary parts of the dynamical dielectric function, including excitonic effects, reveal the highly anisotropic optical feature of the Janus single-layer. A tight-binding (TB) model is also presented for Janus single-layer b-AsP, and it is shown that, with up to seven nearest hoppings, the TB model reproduces well the DFT band structure in the low-energy region around the band gap. This TB model can be used in combination with the Green's function approach to study, e.g., quantum transport in finite systems based on Janus single-layer b-AsP. Furthermore, the linear-elastic properties of Janus single-layer b-AsP are investigated, and the orientation-dependent in-plane stiffness and Poisson ratio are calculated. It is found that the Janus single layer exhibits strong in-plane anisotropy in its Poisson ratio much larger than that of single-layer b-P. This Janus single layer is relevant for promising applications in optical dichroism and anisotropic nanoelasticity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000524531900001 Publication Date 2020-04-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.7 Times cited 30 Open Access  
  Notes ; This work was supported by the German Science Foundation (DFG) within SFB/TRR80 (project G3) and the FLAGERA project TRANS-2D-TMD. M.Y. was supported by a postdoctoral fellowship from the Flemish Science Foundation (FWO-Vl). Computational resources were provided by the Flemish Supercomputer Center (VSC) and Leibniz Supercomputer Centrum (project pr87ro). ; Approved Most recent IF: 3.7; 2020 IF: 3.836  
  Call Number UA @ admin @ c:irua:168554 Serial 6602  
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Author Yagmurcukardes, M.; Peeters, F.M. url  doi
openurl 
  Title Stable single layer of Janus MoSO: strong out-of-plane piezoelectricity Type A1 Journal article
  Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 101 Issue 15 Pages 155205-155208  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using density functional theory based first-principles calculations, we predict the dynamically stable 1H phase of a Janus single layer composed of S-Mo-O atomic layers. It is an indirect band gap semiconductor exhibiting strong polarization arising from the charge difference on the two surfaces. In contrast to 1H phases of MoS2 and MoO2, Janus MoSO is found to possess four Raman active phonon modes and a large out-of-plane piezoelectric coefficient which is absent in fully symmetric single layers of MoS2 and MoO2. We investigated the electronic and phononic properties under applied biaxial strain and found an electronic phase transition with tensile strain while the conduction band edge displays a shift when under compressive strain. Furthermore, single-layer MoSO exhibits phononic stability up to 5% of compressive and 11% of tensile strain with significant phonon shifts. The phonon instability is shown to arise from the soft in-plane and out-of-plane acoustic modes at finite wave vector. The large strain tolerance of Janus MoSO is important for nanoelastic applications. In view of the dynamical stability even under moderate strain, we expect that Janus MoSO can be fabricated in the common 1H phase with a strong out-of-plane piezoelectric coefficient.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000528507900003 Publication Date 2020-04-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.7 Times cited 49 Open Access  
  Notes ; Computational resources were provided by the Flemish Supercomputer Center (VSC). M.Y. is supported by the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. ; Approved Most recent IF: 3.7; 2020 IF: 3.836  
  Call Number UA @ admin @ c:irua:169566 Serial 6614  
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Author Shekarforoush, S.; Jalali, H.; Yagmurcukardes, M.; Milošević, M.V.; Neek-Amal, M. url  doi
openurl 
  Title Optoelectronic properties of confined water in angstrom-scale slits Type A1 Journal article
  Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 102 Issue 23 Pages 235406  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The optoelectronic properties of confined water form one of the most active research areas in the past few years. Here we present the multiscale methodology to discern the out-of-plane electronic and dipolar dielectric constants (epsilon(el)(perpendicular to) and epsilon(diP)(perpendicular to)) of strongly confined water. We reveal that epsilon(perpendicular to el) and epsilon(diP)(perpendicular to) become comparable for water confined in angstrom-scale channels (with a height of less than 15 angstrom) within graphene (GE) and hexagonal boron nitride (hBN) bilayers. Channel height (h) associated with a minimum in both epsilon(e)(l)(perpendicular to) and epsilon(dip)(perpendicular to) is linked to the formation of the ordered structure of ice for h approximate to (7 -7.5) angstrom. The recently measured total dielectric constant epsilon(T)(perpendicular to) of nanoconfined water [L. Fumagalli et al., Science 360, 1339 (2018)] is corroborated by our results. Furthermore, we evaluate the contribution from the encapsulating membranes to the dielectric properties, as a function of the interlayer spacing, i.e., the height of the confining channel for water. Finally, we conduct analysis of the optical properties of both confined water and GE membranes, and show that the electron energy loss function of confined water strongly differs from that of bulk water.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000595856100004 Publication Date 2020-12-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.7 Times cited 1 Open Access  
  Notes ; This work was supported by the Research Foundation – Flanders (FWO). M.Y. gratefully acknowledges his FWO postdoctoral mandate. ; Approved Most recent IF: 3.7; 2020 IF: 3.836  
  Call Number UA @ admin @ c:irua:175051 Serial 6695  
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Author Yagmurcukardes, M.; Senger, R.T.; Peeters, F.M.; Sahin, H. url  doi
openurl 
  Title Mechanical properties of monolayer GaS and GaSe crystals Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 94 Issue 94 Pages 245407  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The mechanical properties of monolayer GaS and GaSe crystals are investigated in terms of their elastic constants: in-plane stiffness (C), Poisson ratio (nu), and ultimate strength (sigma(U)) by means of first-principles calculations. The calculated elastic constants are compared with those of graphene and monolayer MoS2. Our results indicate that monolayer GaS is a stiffer material than monolayer GaSe crystals due to the more ionic character of the Ga-S bonds than the Ga-Se bonds. Although their Poisson ratio values are very close to each other, 0.26 and 0.25 for GaS and GaSe, respectively, monolayer GaS is a stronger material than monolayer GaSe due to its slightly higher sU value. However, GaS and GaSe crystals are found to be more ductile and flexible materials than graphene and MoS2. We have also analyzed the band-gap response of GaS and GaSe monolayers to biaxial tensile strain and predicted a semiconductor-metal crossover after 17% and 14% applied strain, respectively, for monolayer GaS and GaSe. In addition, we investigated how the mechanical properties are affected by charging. We found that the flexibility of single layer GaS and GaSe displays a sharp increase under 0.1e/cell charging due to the repulsive interactions between extra charges located on chalcogen atoms. These charging-controllable mechanical properties of single layers of GaS and GaSe can be of potential use for electromechanical applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000389503400008 Publication Date 2016-12-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9950;2469-9969; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 108 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. R.T.S. acknowledges the support from TUBITAK through project 114F397. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:139229 Serial 4356  
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Author Yagmurcukardes, M.; Torun, E.; Senger, R.T.; Peeters, F.M.; Sahin, H. url  doi
openurl 
  Title Mg(OH)2-WS2 van der Waals heterobilayer : electric field tunable band-gap crossover Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 94 Issue 94 Pages 195403  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Magnesium hydroxide [Mg(OH)(2)] has a layered brucitelike structure in its bulk form and was recently isolated as a new member of two-dimensional monolayer materials. We investigated the electronic and optical properties of monolayer crystals of Mg(OH)(2) and WS2 and their possible heterobilayer structure by means of first-principles calculations. It was found that both monolayers of Mg(OH)(2) and WS2 are direct-gap semiconductors and these two monolayers form a typical van der Waals heterostructure with a weak interlayer interaction and a type-II band alignment with a staggered gap that spatially separates electrons and holes. We also showed that an out-of-plane electric field induces a transition from a staggered to a straddling-type heterojunction. Moreover, by solving the Bethe-Salpeter equation on top of single-shot G(0)W(0) calculations, we show that the low-energy spectrum of the heterobilayer is dominated by the intralyer excitons of the WS2 monolayer. Because of the staggered interfacial gap and the field-tunable energy-band structure, the Mg(OH)(2)-WS2 heterobilayer can become an important candidate for various optoelectronic device applications in nanoscale.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000386769400007 Publication Date 2016-11-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9950;2469-9969; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 38 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. is supported by a FWOPegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge support from TUBITAK through Project No. 114F397. H.S. acknowledges support from Bilim Akademisi – The Science Academy, Turkey, under the BAGEP program. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:138205 Serial 4364  
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Author Yagmurcukardes, M.; Bacaksiz, C.; Unsal, E.; Akbali, B.; Senger, R.T.; Sahin, H. url  doi
openurl 
  Title Strain mapping in single-layer two-dimensional crystals via Raman activity Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 97 Issue 11 Pages 115427  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By performing density functional theory-based ab initio calculations, Raman-active phonon modes of single-layer two-dimensional (2D) materials and the effect of in-plane biaxial strain on the peak frequencies and corresponding activities of the Raman-active modes are calculated. Our findings confirm the Raman spectrum of the unstrained 2D crystals and provide expected variations in the Raman-active modes of the crystals under in-plane biaxial strain. The results are summarized as follows: (i) frequencies of the phonon modes soften (harden) under applied tensile (compressive) strains; (ii) the response of the Raman activities to applied strain for the in-plane and out-of-plane vibrational modes have opposite trends, thus, the built-in strains in the materials can be monitored by tracking the relative activities of those modes; (iii) in particular, the A peak in single-layer Si and Ge disappears under a critical tensile strain; (iv) especially in mono-and diatomic single layers, the shift of the peak frequencies is a stronger indication of the strain rather than the change in Raman activities; (v) Raman-active modes of single-layer ReX2 (X = S, Se) are almost irresponsive to the applied strain. Strain-induced modifications in the Raman spectrum of 2D materials in terms of the peak positions and the relative Raman activities of the modes could be a convenient tool for characterization.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos 000427799300006 Publication Date 2018-03-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 21 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 116C073. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:150840UA @ admin @ c:irua:150840 Serial 4979  
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Author Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. url  doi
openurl 
  Title Electronic and vibrational properties of PbI2: From bulk to monolayer Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 8 Pages 085431  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations, we study the dependence of the electronic and vibrational properties of multilayered PbI2 crystals on the number of layers and focus on the electronic-band structure and the Raman spectrum. Electronic-band structure calculations reveal that the direct or indirect semiconducting behavior of PbI2 is strongly influenced by the number of layers. We find that at 3L thickness there is a direct-to-indirect band gap transition (from bulk-to-monolayer). It is shown that in the Raman spectrum two prominent peaks, A(1g) and E-g, exhibit phonon hardening with an increasing number of layers due to the interlayer van der Waals interaction. Moreover, the Raman activity of the A(1g) mode significantly increases with an increasing number of layers due to the enhanced out-of-plane dielectric constant in the few-layer case. We further characterize rigid-layer vibrations of low-frequency interlayer shear (C) and breathing (LB) modes in few-layer PbI2. A reduced monatomic (linear) chain model (LCM) provides a fairly accurate picture of the number of layers dependence of the low-frequency modes and it is shown also to be a powerful tool to study the interlayer coupling strength in layered PbI2.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos 000442667200008 Publication Date 2018-08-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 41 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. Part of this work was supported by FLAG-ERA project TRANS-2D-TMD. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:153716UA @ admin @ c:irua:153716 Serial 5097  
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Author Yagmurcukardes, M.; Ozen, S.; Iyikanat, F.; Peeters, F.M.; Sahin, H. url  doi
openurl 
  Title Raman fingerprint of stacking order in HfS2-Ca(OH)(2) heterobilayer Type A1 Journal article
  Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 99 Issue 20 Pages 205405  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using density functional theory-based first-principles calculations, we investigate the stacking order dependence of the electronic and vibrational properties of HfS2-Ca(OH)(2) heterobilayer structures. It is shown that while the different stacking types exhibit similar electronic and optical properties, they are distinguishable from each other in terms of their vibrational properties. Our findings on the vibrational properties are the following: (i) from the interlayer shear (SM) and layer breathing (LBM) modes we are able to deduce the AB' stacking order, (ii) in addition, the AB' stacking type can also be identified via the phonon softening of E-g(I) and A(g)(III) modes which harden in the other two stacking types, and (iii) importantly, the ultrahigh frequency regime possesses distinctive properties from which we can distinguish between all stacking types. Moreover, the differences in optical and vibrational properties of various stacking types are driven by two physical effects, induced biaxial strain on the layers and the layer-layer interaction. Our results reveal that with both the phonon frequencies and corresponding activities, the Raman spectrum possesses distinctive properties for monitoring the stacking type in novel vertical heterostructures constructed by alkaline-earth-metal hydroxides.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000467387800010 Publication Date 2019-05-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 23 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under the Project No. 117F095. H.S. acknowledges support from Turkish Academy of Sciences under the GEBIP program. This work is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:160334 Serial 5226  
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Author Yagmurcukardes, M.; Sevik, C.; Peeters, F.M. url  doi
openurl 
  Title Electronic, vibrational, elastic, and piezoelectric properties of monolayer Janus MoSTe phases: A first-principles study Type A1 Journal article
  Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 100 Issue 4 Pages 045415  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By performing density functional theory based first-principles calculations, the electronic, vibrational, elastic, and piezoelectric properties of two dynamically stable crystal phases of monolayer Janus MoSTe, namely 1H-MoSTe and 1T'-MoSTe, are investigated. Vibrational frequency analysis reveals that the other possible crystal structure, 1T-MoSTe, of this Janus monolayer does not exhibit dynamical stability. The 1H-MoSTe phase is found to be an indirect band-gap semiconductor while 1T'-MoSTe is predicted as small-gap semiconductor. Notably, in contrast to the direct band-gap nature of monolayers 1H-MoS2 and 1H-MoTe2, 1H-MoSTe is found to be an indirect gap semiconductor driven by the induced surface strains on each side of the structure. The calculated Raman spectrum of each structure shows unique character enabling us to clearly distinguish the stable crystal phases via Raman measurements. The systematic piezoelectric stress and strain coefficient analysis reveals that out-of-plane piezoelectricity appears in 1H-MoSTe and the noncentral symmetric 1T'-MoSTe has large piezoelectric coefficients. Static total-energy calculations show clearly that the formation of 1T'-MoSTe is feasible by using 1T'-MoTe2 as a basis monolayer. Therefore, we propose that the Janus MoSTe structure can be fabricated in two dynamically stable phases which possess unique electronic, dynamical, and piezoelectric properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000476687800003 Publication Date 2019-07-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 91 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). This work was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:161899 Serial 5411  
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Author Yagmurcukardes, M. url  doi
openurl 
  Title Monolayer fluoro-InSe : formation of a thin monolayer via fluorination of InSe Type A1 Journal article
  Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 100 Issue 2 Pages 024108  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By performing density functional theory-based first-principles calculations, the formation of a thin monolayer structure, namely InSeF, via fluorination of monolayer InSe is predicted. It is shown that strong interaction of F and In atoms leads to the detachment of In-Se layers in monolayer InSe and 1T-like monolayer InSeF structure is formed. Monolayer InSeF is found to be dynamically stable in terms of its phonon band dispersions. In addition, its Raman spectrum is shown to exhibit totally distinctive features as compared to monolayer InSe. The electronic band dispersions reveal that monolayer InSeF is a direct gap semiconductor whose valence and conduction band edges reside at the Gamma point. Moreover, the orientation-dependent linear elastic properties of monolayer InSeF are investigated in terms of the in-plane stiffness and Poisson ratio. It is found that monolayer InSeF displays strong in-plane anisotropy in elastic constants and it is slightly softer material as compared to monolayer InSe. Overall, it is proposed that a thin, direct gap semiconducting monolayer InSeF can be formed by full fluorination of monolayer InSe as a new member of the two-dimensional family.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000477885700003 Publication Date 2019-07-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 9 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). This work is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:161891 Serial 5423  
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Author Ceyhan, E.; Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. doi  openurl
  Title Electronic and magnetic properties of single-layer FeCl₂ with defects Type A1 Journal article
  Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 103 Issue 1 Pages 014106  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The formation of lattice defects and their effect on the electronic properties of single-layer FeCl2 are investigated by means of first-principles calculations. Among the vacancy defects, namely mono-, di-, and three-Cl vacancies and mono-Fe vacancy, the formation of mono-Cl vacancy is the most preferable. Comparison of two different antisite defects reveals that the formation of the Fe-antisite defect is energetically preferable to the Cl-antisite defect. While a single Cl vacancy leads to a 1 mu(B) decrease in the total magnetic moment of the host lattice, each Fe vacant site reduces the magnetic moment by 4 mu(B). However, adsorption of an excess Cl atom on the surface changes the electronic structure to a ferromagnetic metal or to a ferromagnetic semiconductor depending on the adsorption site without changing the ferromagnetic state of the host lattice. Both Cl-antisite and Fe-antisite defected domains change the magnetic moment of the host lattice by -1 mu(B) and +3 mu(B), respectively. The electronic ground state of defected structures reveals that (i) single-layer FeCl2 exhibits half-metallicity under the formation of vacancy and Cl-antisite defects; (ii) ferromagnetic metallicity is obtained when a single Cl atom is adsorbed on upper-Cl and Fe sites, respectively; and (iii) ferromagnetic semiconducting behavior is found when a Cl atom is adsorbed on a lower-Cl site or a Fe-antisite defect is formed. Simulated scanning electron microscope images show that atomic-scale identification of defect types is possible from their electronic charge density. Further investigation of the periodically Fe-defected structures reveals that the formation of the single-layer FeCl3 phase, which is a dynamically stable antiferromagnetic semiconductor, is possible. Our comprehensive analysis on defects in single-layer FeCl2 will complement forthcoming experimental observations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000606969400002 Publication Date 2021-01-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 5 Open Access Not_Open_Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and by Flemish Supercomputer Center (VSC). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. M.Y. was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship. ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:176039 Serial 6689  
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Author Varjovi, M.J.; Yagmurcukardes, M.; Peeters, F.M.; Durgun, E. doi  openurl
  Title Janus two-dimensional transition metal dichalcogenide oxides: First-principles investigation of WXO monolayers with X = S, Se, and Te Type A1 Journal article
  Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 103 Issue 19 Pages 195438  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Structural symmetry breaking in two-dimensional materials can lead to superior physical properties and introduce an additional degree of piezoelectricity. In the present paper, we propose three structural phases (1H, 1T, and 1T') of Janus WXO (X = S, Se, and Te) monolayers and investigate their vibrational, thermal, elastic, piezoelectric, and electronic properties by using first-principles methods. Phonon spectra analysis reveals that while the 1H phase is dynamically stable, the 1T phase exhibits imaginary frequencies and transforms to the distorted 1T' phase. Ab initio molecular dynamics simulations confirm that 1H- and 1T'-WXO monolayers are thermally stable even at high temperatures without any significant structural deformations. Different from binary systems, additional Raman active modes appear upon the formation of Janus monolayers. Although the mechanical properties of 1H-WXO are found to be isotropic, they are orientation dependent for 1T'-WXO. It is also shown that 1H-WXO monolayers are indirect band-gap semiconductors and the band gap narrows down the chalcogen group. Except 1T'-WSO, 1T'-WXO monolayers have a narrow band gap correlated with the Peierls distortion. The effect of spin-orbit coupling on the band structure is also examined for both phases and the alteration in the band gap is estimated. The versatile mechanical and electronic properties of Janus WXO monolayers together with their large piezoelectric response imply that these systems are interesting for several nanoelectronic applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000655902600004 Publication Date 2021-05-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 48 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:179050 Serial 7000  
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Author Yagmurcukardes, M.; Mogulkoc, Y.; Akgenc, B.; Mogulkoc, A.; Peeters, F.M. doi  openurl
  Title Prediction of monoclinic single-layer Janus Ga₂ Te X (X = S and Se) : strong in-plane anisotropy Type A1 Journal article
  Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 104 Issue 4 Pages 045425  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By using density functional theory (DFT) based first-principles calculations, electronic, vibrational, piezo-electric, and optical properties of monoclinic Janus single-layer Ga2TeX (X = S or Se) are investigated. The dynamical, mechanical, and thermal stability of the proposed Janus single layers are verified by means of phonon bands, stiffness tensor, and quantum molecular dynamics simulations. The calculated vibrational spectrum reveals the either pure or coupled optical phonon branches arising from Ga-Te and Ga-X atoms. In addition to the in-plane anisotropy, single-layer Janus Ga2TeX exhibits additional out-of-plane asymmetry, which leads to important consequences for its electronic and optical properties. Electronic band dispersions indicate the direct band-gap semiconducting nature of the constructed Janus structures with energy band gaps falling into visible spectrum. Moreover, while orientation-dependent linear-elastic properties of Janus single layers indicate their strong anisotropy, the calculated in-plane stiffness values reveal the ultrasoft nature of the structures. In addition, predicted piezoelectric coefficients show that while there is a strong in-plane anisotropy between piezoelectric constants along armchair (AC) and zigzag (ZZ) directions, there exists a tiny polarization along the out-of-plane direction as a result of the formation of Janus structure. The optical response to electromagnetic radiation has been also analyzed through density functional theory by considering the independent-particle approximation. Finally, the optical spectra of Janus Ga2TeX structures is investigated and it showed a shift from the ultraviolet region to the visible region. The fact that the spectrum is between these regions will allow it to be used in solar energy and many nanoelectronics applications. The predicted monoclinic single-layer Janus Ga2TeX are relevant for promising applications in optoelectronics, optical dichroism, and anisotropic nanoelasticity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000678811100007 Publication Date 2021-07-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 3.836 Times cited 3 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:180404 Serial 7013  
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Author Yagmurcukardes, M.; Horzum, S.; Torun, E.; Peeters, F.M.; Senger, R.T. url  doi
openurl 
  Title Nitrogenated, phosphorated and arsenicated monolayer holey graphenes Type A1 Journal article
  Year 2016 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 18 Issue 18 Pages 3144-3150  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by a recent experiment that reported the synthesis of a new 2D material nitrogenated holey graphene (C2N) [Mahmood et al., Nat. Commun., 2015, 6, 6486], the electronic, magnetic, and mechanical properties of nitrogenated (C2N), phosphorated (C2P) and arsenicated (C2As) monolayer holey graphene structures are investigated using first-principles calculations. Our total energy calculations indicate that, similar to the C2N monolayer, the formation of the other two holey structures are also energetically feasible. Calculated cohesive energies for each monolayer show a decreasing trend going from the C2N to C2As structure. Remarkably, all the holey monolayers considered are direct band gap semiconductors. Regarding the mechanical properties (in-plane stiffness and Poisson ratio), we find that C2N has the highest in-plane stiffness and the largest Poisson ratio among the three monolayers. In addition, our calculations reveal that for the C2N, C2P and C2As monolayers, creation of N and P defects changes the semiconducting behavior to a metallic ground state while the inclusion of double H impurities in all holey structures results in magnetic ground states. As an alternative to the experimentally synthesized C2N, C2P and C2As are mechanically stable and flexible semiconductors which are important for potential applications in optoelectronics.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000369506000095 Publication Date 2015-12-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 4.123 Times cited 36 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; Approved Most recent IF: 4.123  
  Call Number UA @ lucian @ c:irua:132313 Serial 4214  
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Author Nakhaee, M.; Yagmurcukardes, M.; Ketabi, S.A.; Peeters, F.M. pdf  doi
openurl 
  Title Single-layer structures of a100- and b010-Gallenene : a tight-binding approach Type A1 Journal article
  Year 2019 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 21 Issue 28 Pages 15798-15804  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using the simplified linear combination of atomic orbitals (LCAO) method in combination with ab initio calculations, we construct a tight-binding (TB) model for two different crystal structures of monolayer gallium: a(100)- and b(010)-Gallenene. The analytical expression for the Hamiltonian and numerical results for the overlap matrix elements between different orbitals of the Ga atoms and for the Slater and Koster (SK) integrals are obtained. We find that the compaction of different structures affects significantly the formation of the orbitals. The results for a(100)-Gallenene can be very well explained with an orthogonal basis set, while for b(010)-Gallenene we have to assume a non-orthogonal basis set in order to construct the TB model. Moreover, the transmission properties of nanoribbons of both monolayers oriented along the AC and ZZ directions are also investigated and it is shown that both AC- and ZZ-b(010)-Gallenene nanoribbons exhibit semiconducting behavior with zero transmission while those of a(100)-Gallenene nanoribbons are metallic.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000476603700057 Publication Date 2019-06-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 4.123 Times cited 7 Open Access  
  Notes ; This work is supported by the Methusalem program of the Flemish government and the FLAG-ERA project TRANS-2D-TMD. This work is supported by the Flemish Science Foundation (FWO-Vl) by a post-doctoral fellowship (M. Y.). M. N. is partially supported by BFO (Uantwerpen). ; Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:161881 Serial 5427  
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