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Author Baskurt, M.; Nair, R.R.; Peeters, F.M.; Sahin, H.
Title Ultra-thin structures of manganese fluorides : conversion from manganese dichalcogenides by fluorination Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal (down) Phys Chem Chem Phys
Volume 23 Issue 17 Pages 10218-10224
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In this study, it is predicted by density functional theory calculations that graphene-like novel ultra-thin phases of manganese fluoride crystals, that have nonlayered structures in their bulk form, can be stabilized by fluorination of manganese dichalcogenide crystals. First, it is shown that substitution of fluorine atoms with chalcogens in the manganese dichalcogenide host lattice is favorable. Among possible crystal formations, three stable ultra-thin structures of manganese fluoride, 1H-MnF2, 1T-MnF2 and MnF3, are found to be stable by total energy optimization calculations. In addition, phonon calculations and Raman activity analysis reveal that predicted novel single-layers are dynamically stable crystal structures displaying distinctive characteristic peaks in their vibrational spectrum enabling experimental determination of the corresponding phases. Differing from 1H-MnF2 antiferromagnetic (AFM) large gap semiconductor, 1T-MnF2 and MnF3 single-layers are semiconductors with ferromagnetic (FM) ground state.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000641719700001 Publication Date 2021-04-15
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 4.123 Times cited 1 Open Access Not_Open_Access
Notes Approved Most recent IF: 4.123
Call Number UA @ admin @ c:irua:178252 Serial 7043
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Author Sozen, Y.; Yagmurcukardes, M.; Sahin, H.
Title Vibrational and optical identification of GeO₂ and GeO single layers : a first-principles study Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal (down) Phys Chem Chem Phys
Volume 23 Issue 37 Pages 21307-21315
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In the present work, the identification of two hexagonal phases of germanium oxides (namely GeO2 and GeO) through the vibrational and optical properties is reported using density functional theory calculations. While structural optimizations show that single-layer GeO2 and GeO crystallize in 1T and buckled phases, phonon band dispersions reveal the dynamical stability of each structure. First-order off-resonant Raman spectral predictions demonstrate that each free-standing single-layer possesses characteristic peaks that are representative for the identification of the germanium oxide phase. On the other hand, electronic band dispersion analysis shows the insulating and large-gap semiconducting nature of single-layer GeO2 and GeO, respectively. Moreover, optical absorption, reflectance, and transmittance spectra obtained by means of G(0)W(0)-BSE calculations reveal the existence of tightly bound excitons in each phase, displaying strong optical absorption. Furthermore, the excitonic gaps are found to be at deep UV and visible portions of the spectrum, for GeO2 and GeO crystals, with energies of 6.24 and 3.10 eV, respectively. In addition, at the prominent excitonic resonances, single-layers display high reflectivity with a zero transmittance, which is another indication of the strong light-matter interaction inside the crystal medium.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000697364300001 Publication Date 2021-09-02
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 4.123 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 4.123
Call Number UA @ admin @ c:irua:181571 Serial 7044
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Author Tongay, S.; Sahin, H.; Ko, C.; Luce, A.; Fan, W.; Liu, K.; Zhou, J.; Huang, Y.S.; Ho, C.H.; Yan, J.; Ogletree, D.F.; Aloni, S.; Ji, J.; Li, S.; Li, J.; Peeters, F.M.; Wu, J.;
Title Monolayer behaviour in bulk ReS2 due to electronic and vibrational decoupling Type A1 Journal article
Year 2014 Publication Nature communications Abbreviated Journal (down) Nat Commun
Volume 5 Issue Pages 3252
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Semiconducting transition metal dichalcogenides consist of monolayers held together by weak forces where the layers are electronically and vibrationally coupled. Isolated monolayers show changes in electronic structure and lattice vibration energies, including a transition from indirect to direct bandgap. Here we present a new member of the family, rhenium disulphide (ReS2), where such variation is absent and bulk behaves as electronically and vibrationally decoupled monolayers stacked together. From bulk to monolayers, ReS2 remains direct bandgap and its Raman spectrum shows no dependence on the number of layers. Interlayer decoupling is further demonstrated by the insensitivity of the optical absorption and Raman spectrum to interlayer distance modulated by hydrostatic pressure. Theoretical calculations attribute the decoupling to Peierls distortion of the 1T structure of ReS2, which prevents ordered stacking and minimizes the interlayer overlap of wavefunctions. Such vanishing interlayer coupling enables probing of two-dimensional-like systems without the need for monolayers.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000332666700010 Publication Date 2014-02-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 806 Open Access
Notes ; This work was supported by the United States Department of Energy Early Career Award DE-FG02-11ER46796. The high pressure part of this work was supported by COMPRES, the Consortium for Materials Properties Research in Earth Sciences, under National Science Foundation Cooperative Agreement EAR 11-577758. The electron microscopy and nano-Auger measurements were supported by the user programme at the Molecular Foundry, which was supported by the Office of Science, Office of Basic Energy Sciences, of the United States Department of Energy under contract no. DE-AC02-05CH11231. S. A. gratefully acknowledges Dr Virginia Altoe of the Molecular Foundry for help with the TEM data acquisition and analysis. J.L. acknowledges support from the Natural Science Foundation of China for Distinguished Young Scholar (grant nos. 60925016 and 91233120). Y.-S.H. and C.-H. H. acknowledge support from the National Science Council of Taiwan under project nos. NSC 100-2112-M-011-001-MY3 and NSC 101-2221-E-011-052-MY3. H. S. was supported by the FWO Pegasus Marie Curie Long Fellowship programme. The DFT work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem programme of the Flemish government. Computational resources were partially provided by TUBITAK ULAKBIM, High Performance and Grid Computing Centre. ; Approved Most recent IF: 12.124; 2014 IF: 11.470
Call Number UA @ lucian @ c:irua:119247 Serial 2192
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Author Wu, K.; Torun, E.; Sahin, H.; Chen, B.; Fan, X.; Pant, A.; Wright, D.P.; Aoki, T.; Peeters, F.M.; Soignard, E.; Tongay, S.
Title Unusual lattice vibration characteristics in whiskers of the pseudo-one-dimensional titanium trisulfide TiS3 Type A1 Journal article
Year 2016 Publication Nature communications Abbreviated Journal (down) Nat Commun
Volume 7 Issue Pages 12952
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Transition metal trichalcogenides form a class of layered materials with strong in-plane anisotropy. For example, titanium trisulfide (TiS3) whiskers are made out of weakly interacting TiS3 layers, where each layer is made of weakly interacting quasi-one-dimensional chains extending along the b axis. Here we establish the unusual vibrational properties of TiS3 both experimentally and theoretically. Unlike other two-dimensional systems, the Raman active peaks of TiS3 have only out-of-plane vibrational modes, and interestingly some of these vibrations involve unique rigid-chain vibrations and S-S molecular oscillations. High-pressure Raman studies further reveal that the A(g)(S-S) S-S molecular mode has an unconventional negative pressure dependence, whereas other peaks stiffen as anticipated. Various vibrational modes are doubly degenerate at ambient pressure, but the degeneracy is lifted at high pressures. These results establish the unusual vibrational properties of TiS3 with strong in-plane anisotropy, and may have relevance to understanding of vibrational properties in other anisotropic two-dimensional material systems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000385444300004 Publication Date 2016-09-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 50 Open Access
Notes ; S.T. acknowledges support from the National Science Foundation (DMR-1552220) and (CMMI-1561839). F.M.P., H.S. and E.T. were supported by the Flemish Science Foundation (FWO-Vl). Computational resources were partially 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 programme. F.P. acknowledges the funding from Flemish Science Foundation (FWO-Vl). K.W. acknowledges helpful discussions with H. Cai, W. Kong and X. Meng. We gratefully acknowledge the use of facilities within the LeRoy Eyring Center for Solid State Science at Arizona State University. ; Approved Most recent IF: 12.124
Call Number UA @ lucian @ c:irua:144662 Serial 4700
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Author Cai, H.; Kang, J.; Sahin, H.; Chen, B.; Suslu, A.; Wu, K.; Peeters, F.; Meng, X.; Tongay, S.
Title Exciton pumping across type-I gallium chalcogenide heterojunctions Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal (down) Nanotechnology
Volume 27 Issue 27 Pages 065203
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Quasi-two-dimensional gallium chalcogenide heterostructures are created by transferring exfoliated few-layer GaSe onto bulk GaTe sheets. Luminescence spectroscopy measurements reveal that the light emission from underlying GaTe layers drastically increases on heterojunction regions where GaSe layers make contact with the GaTe. Density functional theory (DFT) and band offset calculations show that conduction band minimum (CBM) (valance band maximum (VBM)) values of GaSe are higher (lower) in energy compared to GaTe, forming type-I band alignment at the interface. Consequently, GaSe layers provide photo-excited electrons and holes to GaTe sheets through relatively large built-in potential at the interface, increasing overall exciton population and light emission from GaTe. Observed results are not specific to the GaSe/GaTe system but observed on GaS/GaSe heterolayers with type-I band alignment. Observed experimental findings and theoretical studies provide unique insights into interface effects across dissimilar gallium chalcogenides and offer new ways to boost optical performance by simple epitaxial coating.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000368897100008 Publication Date 2016-01-13
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 3.44 Times cited 15 Open Access
Notes ; This work was supported by the Arizona State University seeding program, the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of the John M Cowley Center for High Resolution Electron Microscopy at Arizona State University. The authors thank Anupum Pant for useful discussions. We gratefully acknowledge the use of the facilities at the LeRoy Eyring Center for Solid State Science at Arizona State University. S Tongay acknowledges support from DMR-1552220. ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:131570 Serial 4179
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Author Kiymaz, D.; Yagmurcukardes, M.; Tomak, A.; Sahin, H.; Senger, R.T.; Peeters, F.M.; Zareie, H.M.; Zafer, C.
Title Controlled growth mechanism of poly (3-hexylthiophene) nanowires Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal (down) 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 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 Tomak, A.; Bacaksiz, C.; Mendirek, G.; Sahin, H.; Hur, D.; Gorgun, K.; Senger, R.T.; Birer, O.; Peeters, F.M.; Zareie, H.M.
Title Structural changes in a Schiff base molecular assembly initiated by scanning tunneling microscopy tip Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal (down) Nanotechnology
Volume 27 Issue 27 Pages 335601
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We report the controlled self-organization and switching of newly designed Schiff base (E)-4-((4-(phenylethynyl) benzylidene) amino) benzenethiol (EPBB) molecules on a Au (111) surface at room temperature. Scanning tunneling microscopy and spectroscopy (STM/STS) were used to image and analyze the conformational changes of the EPBB molecules. The conformational change of the molecules was induced by using the STM tip while increasing the tunneling current. The switching of a domain or island of molecules was shown to be induced by the STM tip during scanning. Unambiguous fingerprints of the switching mechanism were observed via STM/STS measurements. Surface-enhanced Raman scattering was employed, to control and identify quantitatively the switching mechanism of molecules in a monolayer. Density functional theory calculations were also performed in order to understand the microscopic details of the switching mechanism. These calculations revealed that the molecular switching behavior stemmed from the strong interaction of the EPBB molecules with the STM tip. Our approach to controlling intermolecular mechanics provides a path towards the bottom-up assembly of more sophisticated molecular machines.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000383780500012 Publication Date 2016-07-05
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 3.44 Times cited 2 Open Access
Notes ; The authors acknowledge financial support from TUBITAK (PROJECT NO: 112T507). This work was also supported by the Flemish Science Foundation (FWO-Vl). Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid-Infrastructure). HS is supported by an FWO Pegasus Long Marie Curie Fellowship. ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:137155 Serial 4363
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Author Pant, A.; Torun, E.; Chen, B.; Bhat, S.; Fan, X.; Wu, K.; Wright, D.P.; Peeters, F.M.; Soignard, E.; Sahin, H.; Tongay, S.
Title Strong dichroic emission in the pseudo one dimensional material ZrS3 Type A1 Journal article
Year 2016 Publication Nanoscale Abbreviated Journal (down) Nanoscale
Volume 8 Issue 8 Pages 16259-16265
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Zirconium trisulphide (ZrS3), a member of the layered transition metal trichalcogenides (TMTCs) family, has been studied by angle-resolved photoluminescence spectroscopy (ARPLS). The synthesized ZrS3 layers possess a pseudo one-dimensional nature where each layer consists of ZrS3 chains extending along the b-lattice direction. Our results show that the optical properties of few-layered ZrS3 are highly anisotropic as evidenced by large PL intensity variation with the polarization direction. Light is efficiently absorbed when the E-field is polarized along the chain (b-axis), but the field is greatly attenuated and absorption is reduced when it is polarized vertical to the 1D-like chains as the wavelength of the exciting light is much longer than the width of each 1D chain. The observed PL variation with polarization is similar to that of conventional 1D materials, i.e., nanowires, and nanotubes, except for the fact that here the 1D chains interact with each other giving rise to a unique linear dichroism response that falls between the 2D (planar) and 1D (chain) limit. These results not only mark the very first demonstration of PL polarization anisotropy in 2D systems, but also provide novel insight into how the interaction between adjacent 1D-like chains and the 2D nature of each layer influences the overall optical anisotropy of pseudo-1D materials. Results are anticipated to have an impact on optical technologies such as polarized detectors, near-field imaging, communication systems, and bio-applications relying on the generation and detection of polarized light.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000384531600018 Publication Date 2016-08-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 54 Open Access
Notes ; S. Tongay gratefully acknowledges support from NSF DMR-1552220. 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). HS is supported by a FWO postdoctoral fellowship. ; Approved Most recent IF: 7.367
Call Number UA @ lucian @ c:irua:144656 Serial 4116
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Author Meng, X.; Pant, A.; Cai, H.; Kang, J.; Sahin, H.; Chen, B.; Wu, K.; Yang, S.; Suslu, A.; Peeters, F.M.; Tongay, S.;
Title Engineering excitonic dynamics and environmental stability of post-transition metal chalcogenides by pyridine functionalization technique Type A1 Journal article
Year 2015 Publication Nanoscale Abbreviated Journal (down) Nanoscale
Volume 7 Issue 7 Pages 17109-17115
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract http://cmt.ua.ac.be/hsahin/publishedpapers/46.pdf
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos http://cmt.ua.ac.be/hsahin/publishedpapers/46.pdf Publication Date 2015-09-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364 ISBN Additional Links UA library record; http://cmt.ua.ac.be/hsahin/publishedpapers/46.pdf; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 11 Open Access
Notes ; ; Approved Most recent IF: 7.367; 2015 IF: 7.394
Call Number UA @ lucian @ c:irua:129434 Serial 4175
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Author Yagmurcukardes, M.; Sozen, Y.; Baskurt, M.; Peeters, F.M.; Sahin, H.
Title Interface-dependent phononic and optical properties of GeO/MoSO heterostructures Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal (down) Nanoscale
Volume Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The interface-dependent electronic, vibrational, piezoelectric, and optical properties of van der Waals heterobilayers, formed by buckled GeO (b-GeO) and Janus MoSO structures, are investigated by means of first-principles calculations. The electronic band dispersions show that O/Ge and S/O interface formations result in a type-II band alignment with direct and indirect band gaps, respectively. In contrast, O/O and S/Ge interfaces give rise to the formation of a type-I band alignment with an indirect band gap. By considering the Bethe-Salpeter equation (BSE) on top of G(0)W(0) approximation, it is shown that different interfaces can be distinguished from each other by means of the optical absorption spectra as a consequence of the band alignments. Additionally, the low- and high-frequency regimes of the Raman spectra are also different for each interface type. The alignment of the individual dipoles, which is interface-dependent, either weakens or strengthens the net dipole of the heterobilayers and results in tunable piezoelectric coefficients. The results indicate that the possible heterobilayers of b-GeO/MoSO asymmetric structures possess various electronic, optical, and piezoelectric properties arising from the different interface formations and can be distinguished by means of various spectroscopic techniques.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000738899600001 Publication Date 2021-12-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 5 Open Access Not_Open_Access
Notes Approved Most recent IF: 7.367
Call Number UA @ admin @ c:irua:184722 Serial 6998
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Author Yang, S.; Wang, C.; Sahin, H.; Chen, H.; Li, Y.; Li, S.S.; Suslu, A.; Peeters, F.M.; Liu, Q.; Li, J.; Tongay, S.;
Title Tuning the optical, magnetic, and electrical properties of ReSe2 by nanoscale strain engineering Type A1 Journal article
Year 2015 Publication Nano letters Abbreviated Journal (down) Nano Lett
Volume 15 Issue 15 Pages 1660-1666
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Creating materials with ultimate control over their physical properties is vital for a wide range of applications. From a traditional materials design perspective, this task often requires precise control over the atomic composition and structure. However, owing to their mechanical properties, low-dimensional layered materials can actually withstand a significant amount of strain and thus sustain elastic deformations before fracture. This, in return, presents a unique technique for tuning their physical properties by strain engineering. Here, we find that local strain induced on ReSe2, a new member of the transition metal dichalcogenides family, greatly changes its magnetic, optical, and electrical properties. Local strain induced by generation of wrinkle (1) modulates the optical gap as evidenced by red-shifted photoluminescence peak, (2) enhances light emission, (3) induces magnetism, and (4) modulates the electrical properties. The results not only allow us to create materials with vastly different properties at the nanoscale, but also enable a wide range of applications based on 2D materials, including strain sensors, stretchable electrodes, flexible field-effect transistors, artificial-muscle actuators, solar cells, and other spintronic, electromechanical, piezoelectric, photonic devices.
Address
Corporate Author Thesis
Publisher Place of Publication Washington Editor
Language Wos 000351188000033 Publication Date 2015-02-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984;1530-6992; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 314 Open Access
Notes ; This work is supported by Arizona State University, Research Seeding Program, the National Natural Science Foundation of China (91233120), and the National Basic Research Program of China (2011CB921901). Q., Liu acknowledges the support to this work by NSFC (10974037), NBRPC (2010CB934102), and the CAS Strategy Pilot program (XDA 09020300). S. Yang acknowledges financial support from China Postdoctoral Science Foundation (No. 2013M540127). ; Approved Most recent IF: 12.712; 2015 IF: 13.592
Call Number c:irua:125480 Serial 3758
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Author Sreepal, V.; Yagmurcukardes, M.; Vasu, K.S.; Kelly, D.J.; Taylor, S.F.R.; Kravets, V.G.; Kudrynskyi, Z.; Kovalyuk, Z.D.; Patane, A.; Grigorenko, A.N.; Haigh, S.J.; Hardacre, C.; Eaves, L.; Sahin, H.; Geim, A.K.; Peeters, F.M.; Nair, R.R.
Title Two-dimensional covalent crystals by chemical conversion of thin van der Waals materials Type A1 Journal article
Year 2019 Publication Nano letters Abbreviated Journal (down) Nano Lett
Volume 19 Issue 9 Pages 6475-6481
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Most of the studied two-dimensional (2D) materials have been obtained by exfoliation of van der Waals crystals. Recently, there has been growing interest in fabricating synthetic 2D crystals which have no layered bulk analogues. These efforts have been focused mainly on the surface growth of molecules in high vacuum. Here, we report an approach to making 2D crystals of covalent solids by chemical conversion of van der Waals layers. As an example, we used 2D indium selenide (InSe) obtained by exfoliation and converted it by direct fluorination into indium fluoride (InF3), which has a nonlayered, rhombohedral structure and therefore cannot possibly be obtained by exfoliation. The conversion of InSe into InF3 is found to be feasible for thicknesses down to three layers of InSe, and the obtained stable InF3 layers are doped with selenium. We study this new 2D material by optical, electron transport, and Raman measurements and show that it is a semiconductor with a direct bandgap of 2.2 eV, exhibiting high optical transparency across the visible and infrared spectral ranges. We also demonstrate the scalability of our approach by chemical conversion of large-area, thin InSe laminates obtained by liquid exfoliation, into InF3 films. The concept of chemical conversion of cleavable thin van der Waals crystals into covalently bonded noncleavable ones opens exciting prospects for synthesizing a wide variety of novel atomically thin covalent crystals.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000486361900083 Publication Date 2019-08-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 32 Open Access
Notes ; This work was supported by the Royal Society, the European Research Council (contract 679689 and EvoluTEM 715502), and Engineering and Physical Sciences Research Council, U.K. (EP/N013670/1), The authors acknowledge the use of the facilities at the Henry Royce Institute for Advanced Materials and associated support services. H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. M.Y. acknowledges the Flemish Science Foundation (FWO-Vl) for a postdoctoral fellowship. S.J.H. and D.J.K. acknowledge support from EPSRC (EP/P009050/1) and the NowNANO CDT. ; Approved Most recent IF: 12.712
Call Number UA @ admin @ c:irua:162818 Serial 5431
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Author Gul, A.; Bacaksiz, C.; Unsal, E.; Akbali, B.; Tomak, A.; Zareie, H.M.; Sahin, H.
Title Theoretical and experimental investigation of conjugation of 1,6-hexanedithiol on MoS2 Type A1 Journal article
Year 2018 Publication Materials Research Express Abbreviated Journal (down) Mater Res Express
Volume 5 Issue 3 Pages 036415
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We report an experimental and theoretical investigation of conjugation of 1,6-Hexaneditihiol (HDT) on MoS2 which is prepared by mixing MoS2 structure and HDT molecules in proper solvent. Raman spectra and the calculated phonon bands reveal that the HDT molecules bind covalently to MoS2. Surface morphology of MoS2/HDTstructure is changed upon conjugation ofHDTon MoS2 and characterized by using Scanning Electron Microscope (SEM). Density Functional Theory (DFT) based calculations show that HOMO-LUMO band gap of HDT is altered after the conjugation and two-S binding (handle-like) configuration is energetically most favorable among three different structures. This study displays that the facile thiol functionalization process of MoS2 is promising strategy for obtaining solution processable MoS2.
Address
Corporate Author Thesis
Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos 000428781400003 Publication Date 2018-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2053-1591 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.068 Times cited 2 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 116C073. HS acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. ; Approved Most recent IF: 1.068
Call Number UA @ lucian @ c:irua:154607UA @ admin @ c:irua:154607 Serial 5133
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Author Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M.
Title Giant magnetic anisotropy in doped single layer molybdenum disulfide and fluorographene Type A1 Journal article
Year 2016 Publication Journal of physics : condensed matter Abbreviated Journal (down) J Phys-Condens Mat
Volume 28 Issue 28 Pages 195301
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Stable monolayer materials based on existing, well known and stable two-dimensional crystal fluorographene and molybdenum disulfide are predicted to exhibit a huge magnetocrystalline anisotropy when functionalized with adsorbed transition metal atoms at vacant sides. Ab initio calculations within the density-functional theory formalism were performed to investigate the adsorption of the transitional metals in a single S (or F) vacancy of monolayer molybdenum disulfide (or fluorographene). We found strong bonding of the transitional metal atoms to the vacant sites with binding energies ranging from 2.5 to 5.2 eV. Our calculations revealed that these systems with adsorbed metal atoms exhibit a magnetic anisotropy, specifically the structures including Os and Ir show a giant magnetocrystalline anisotropy energy of 31-101 meV. Our results demonstrate the possibility of obtaining stable monolayer materials with huge magnetocrystalline anisotropy based on preexisting, well known and stable two-dimensional crystals: fluorographene and molybdenum disulfide. We believe that the results obtained here are useful not only for deeper understanding of the origin of magnetocrystalline anisotropy but also for the design of monolayer optoelectronic devices with novel functionalities.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000374394700007 Publication Date 2016-04-13
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 2.649 Times cited 7 Open Access
Notes Approved Most recent IF: 2.649
Call Number UA @ lucian @ c:irua:133611 Serial 4185
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Author Esfahani; Leenaerts, O.; Sahin, H.; Partoens, B.; Peeters, F.M.
Title Structural transitions in monolayer MOS2 by lithium adsorption Type A1 Journal article
Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal (down) J Phys Chem C
Volume 119 Issue 119 Pages 10602-10609
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Based on first-principles calculations, we study the structural stability of the H and T phases of monolayer MoS2 upon Li doping. Our calculations demonstrate that it is possible to stabilize a distorted T phase of MoS2 over the H phase through adsorption of Li atoms on the MoS2 surface. Through molecular dynamics and phonon calculations, we show that the T phase of MoS2 is dynamically unstable and undergoes considerable distortions. The type of distortion depends on the concentration of adsorbed Li atoms and changes from zigzag-like to diamond-like when increasing the Li doping. There exists a substantial energy barrier to transform the stable H phase to the distorted T phases, which is considerably reduced by increasing the concentration of Li atoms. We show that it is necessary that the Li atoms adsorb on both sides of the MoS2 monolayer to reduce the barrier sufficiently. Two processes are examined that allow for such two-sided adsorption, namely, penetration through the MoS2 layer and diffusion over the MoS2 surface. We show that while there is only a small barrier of 0.24 eV for surface diffusion, the amount of energy needed to pass through a pure MoS2 layer is of the order of similar or equal to 2 eV. However, when the MoS2 layer is covered with Li atoms the amount of energy that Li atoms should gain to penetrate the layer is drastically reduced and penetration becomes feasible.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000354912200051 Publication Date 2015-04-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 96 Open Access
Notes ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl) and the Methusalem program of the Flemish government. H. S is supported by an FWO Pegasus-Long Marie Curie fellowship. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government department EWI. ; Approved Most recent IF: 4.536; 2015 IF: 4.772
Call Number c:irua:126409 Serial 3270
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Author Kang, J.; Sahin, H.; Peeters, F.M.
Title Tuning carrier confinement in the MoS2/WS2 lateral heterostructure Type A1 Journal article
Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal (down) J Phys Chem C
Volume 119 Issue 119 Pages 9580-9586
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract To determine and control the spatial confinement of charge carriers is of importance for nanoscale optoelectronic device applications. Using first-principles calculations, we investigate the tunability of band alignment and Charge localization in lateral and combined lateral vertical heterostructures of MoS2 and WS2. First, we Show that a type-II to type-I band alignment transition takes place when tensile strain is applied on the WS2 region. This band alignment transition is a result of the different response of the band edge states with strain and is caused by their different wave function characters. Then we show that the presence of the grain boundary introduces localized in-gap states. The boundary at the armchair interface significantly modifies the charge distribution of the valence band maximum (VBM) state, whereas in a heterostructure with tilt grain domains both conducation band maximum (CBM) and VBM are found to be localized around the grain boundary. We also found that the thickness of the constituents in a lateral heterostructure also determines how the electrons and holes are confined. Creating combined lateral vertical heterostructures of MOS2/WS2 provides another way cif tuning the charge confinement. These results provide possible ways to tune the carrier confinement in MoS2/WS2 heterostructures, which are interesting for its practical: applications in the future.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000353930700066 Publication Date 2015-04-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 73 Open Access
Notes ; This work was supported by the Methusalem program of the Flemish government. H.S. is supported by a FWO Pegasus Marie Curie-long Fellowship and J.K. by a FWO Pegasus Marie Curie-short Fellowship. ; Approved Most recent IF: 4.536; 2015 IF: 4.772
Call Number c:irua:126381 Serial 3747
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Author Iyikanat, F.; Sahin, H.; Senger, R.T.; Peeters, F.M.
Title Vacancy formation and oxidation characteristics of single layer TiS3 Type A1 Journal article
Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal (down) J Phys Chem C
Volume 119 Issue 119 Pages 10709-10715
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The structural, electronic, and magnetic properties of pristine, defective, and oxidized monolayer TiS3 are investigated using first-principles calculations in the framework of density functional theory. We found that a single layer of TiS3 is a direct band gap semiconductor, and the bonding nature of the crystal is fundamentally different from other transition metal chalcogenides. The negatively charged surfaces of single layer TiS3 makes this crystal a promising material for lubrication applications. The formation energies of possible vacancies, i.e. S, Ti, TiS, and double S, are investigated via total energy optimization calculations. We found that the formation of a single S vacancy was the most likely one among the considered vacancy types. While a single S vacancy results in a nonmagnetic, semiconducting character with an enhanced band gap, other vacancy types induce metallic behavior with spin polarization of 0.3-0.8 mu(B). The reactivity of pristine and defective TiS3 crystals against oxidation was investigated using conjugate gradient calculations where we considered the interaction with atomic O, O-2, and O-3. While O-2 has the lowest binding energy with 0.05-0.07 eV, O-3 forms strong bonds stable even at moderate temperatures. The strong interaction (3.9-4.0 eV) between atomic O and TiS3 results in dissociative adsorption of some O-containing molecules. In addition, the presence of S-vacancies enhances the reactivity of the surface with atomic O, whereas it had a negative effect on the reactivity with O-2 and O-3 molecules.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000354912200063 Publication Date 2015-04-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 51 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), and HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. RI., H.S., and R.T.S. acknowledge the support from TUBITAK through project 114F397. ; Approved Most recent IF: 4.536; 2015 IF: 4.772
Call Number c:irua:126410 Serial 3829
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Author Badalov, S.V.; Yagmurcukardes, M.; Peeters, F.M.; Sahin, H.
Title Enhanced stability of single-layer w-Gallenene through hydrogenation Type A1 Journal article
Year 2018 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal (down) J Phys Chem C
Volume 122 Issue 49 Pages 28302-28309
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Using density functional theory based first-principles calculations, the effect of surface hydrogenation on the structural, dynamical, electronic, and mechanical properties of monolayer washboard-gallenene (w-gallenene) is investigated. It is found that the dynamically stabilized strained monolayer of w-gallenene has a metallic nonmagnetic ground state. Both one-sided and two-sided hydrogenations of w-gallenene suppress its dynamical instability even when unstrained. Unlike one-sided hydrogenated monolayer w-gallenene (os-w-gallenene), two-sided hydrogenated monolayer w-gallenene (ts-w-gallenene) possesses the same crystal structure as w-gallenene. Electronic band structure calculations reveal that monolayers of hydrogenated derivatives of w-gallenene exhibit also metallic nonmagnetic ground state. Moreover, the linear-elastic constants, in-plane stiffness and Poisson ratio, are enhanced by hydrogenation, which is opposite to the behavior of other hydrogenated monolayer crystals. Furthermore, monolayer w-gallenene and ts-w-gallenene remain dynamically stable up to relatively higher biaxial strains as compared to borophene. With its enhanced dynamical stability, robust metallic character, and enhanced linear-elastic properties, hydrogenated monolayer w-gallenene is a potential candidate for nanodevice applications as a two-dimensional flexible metal.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000453488300053 Publication Date 2018-11-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 20 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 Turkish Academy of Sciences under the GEBIP program. This work was supported by FLAG-ERA project TRANS-2D-TMD. This work is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: 4.536
Call Number UA @ admin @ c:irua:156229 Serial 5210
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Author Kahraman, Z.; Kandemir, A.; Yagmurcukardes, M.; Sahin, H.
Title Single-layer Janus-type platinum dichalcogenides and their heterostructures Type A1 Journal article
Year 2019 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal (down) J Phys Chem C
Volume 123 Issue 7 Pages 4549-4557
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Ultrathin two-dimensional Janus-type platinum dichalcogenide crystals formed by two different atoms at opposite surfaces are investigated by performing state-of-the-art density functional theory calculations. First, it is shown that single-layer PtX2 structures (where X = S, Se, or Te) crystallize into the dynamically stable IT phase and are indirect band gap semiconductors. It is also found that the substitutional chalcogen doping in all PtX2 structures is favorable via replacement of surface atoms with a smaller chalcogen atom, and such a process leads to the formation of Janus-type platinum dichalcogenides (XPtY, where X and Y stand for S, Se, or Te) which are novel single-layer crystals. While all Janus structures are indirect band gap semiconductors as their binary analogues, their Raman spectra show distinctive features that stem from the broken out-of-plane symmetry. In addition, it is revealed that the construction of Janus crystals enhances the piezoelectric constants of PtX2 crystals significantly both in the in plane and in the out-of-plane directions. Moreover, it is shown that vertically stacked van der Waals heterostructures of binary and ternary (Janus) platinum dichalcogenides offer a wide range of electronic features by forming bilayer heterojunctions of type-I, type-II, and type-III, respectively. Our findings reveal that Janus-type ultrathin platinum dichalcogenide crystals are quite promising materials for optoelectronic device applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000459836900071 Publication Date 2019-01-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 20 Open Access
Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. and Z.K. acknowledge financial support from the TUBITAK under the project number 117F095. This work is supported by the Flemish Science Foundation (FWO-Vl) by a post-doctoral fellowship (M.Y.). H.S. acknowledges support from Turkiye Bilimler Akademisi-Turkish Academy of Sciences under the GEBIP program. ; Approved Most recent IF: 4.536
Call Number UA @ admin @ c:irua:158617 Serial 5229
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Author Eren, I.; Ozen, S.; Sozen, Y.; Yagmurcukardes, M.; Sahin, H.
Title Vertical van der Waals heterostructure of single layer InSe and SiGe Type A1 Journal article
Year 2019 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal (down) J Phys Chem C
Volume 123 Issue 51 Pages 31232-31237
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We present a first-principles investigation on the stability, electronic structure, and mechanical response of ultrathin heterostructures composed of single layers of InSe and SiGe. First, by performing total energy optimization and phonon calculations, we show that single layers of InSe and SiGe can form dynamically stable heterostructures in 12 different stacking types. Valence and conduction band edges of the heterobilayers form a type-I heterojunction having a tiny band gap ranging between 0.09 and 0.48 eV. Calculations on elastic-stiffness tensor reveal that two mechanically soft single layers form a heterostructure which is stiffer than the constituent layers because of relatively strong interlayer interaction. Moreover, phonon analysis shows that the bilayer heterostructure has highly Raman active modes at 205.3 and 43.7 cm(-1), stemming from the out-of-plane interlayer mode and layer breathing mode, respectively. Our results show that, as a stable type-I heterojunction, ultrathin heterobilayer of InSe/SiGe holds promise for nanoscale device applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000505632900050 Publication Date 2019-12-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited Open Access
Notes Approved Most recent IF: 4.536
Call Number UA @ admin @ c:irua:165718 Serial 6332
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Author Kahraman, Z.; Yagmurcukardes, M.; Sahin, H.
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 (down) 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 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 Iyikanat, F.; Yagmurcukardes, M.; Senger, R.T.; Sahin, H.
Title Tuning electronic and magnetic properties of monolayer \alpha-RuCl3 by in-plane strain Type A1 Journal article
Year 2018 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal (down) J Mater Chem C
Volume 6 Issue 8 Pages 2019-2025
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract By employing density functional theory-based methods, the structural, vibrational, electronic, and magnetic properties of monolayer -RuCl3 were investigated. It was demonstrated that ferromagnetic (FM) and zigzag-antiferromagnetic (ZZ-AFM) spin orders in the material have very close total energies with the latter being the ground state. We found that each Ru atom possesses a magnetic moment of 0.9 (B) and the material exhibits strong magnetic anisotropy. While both phases exhibit indirect gaps, the FM phase is a magnetic semiconductor and the ZZ-AFM phase is a non-magnetic semiconductor. The structural stability of the material was confirmed by phonon calculations. Moreover, dynamical analysis revealed that the magnetic order in the material can be monitored via Raman measurements of the crystal structure. In addition, the magnetic ground state of the material changes from ZZ-AFM to FM upon certain applied strains. Valence and conduction band-edges of the material vary considerably under in-plane strains. Owing to the stable lattice structure and unique and controllable magnetic properties, monolayer -RuCl3 is a promising material in nanoscale device applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000426483800015 Publication Date 2018-01-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7526; 2050-7534 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.256 Times cited 16 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 TUBITAK under project number 116C073. H. S. also acknowledges support from Bilim Akademisi-The Science Academy, Turkey, under the BAGEP program. ; Approved Most recent IF: 5.256
Call Number UA @ lucian @ c:irua:149900UA @ admin @ c:irua:149900 Serial 4952
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Author Ghosh, S.; Tongay, S.; Hebard, A.F.; Sahin, H.; Peeters, F.M.
Title Ferromagnetism in stacked bilayers of Pd/C60 Type A1 Journal article
Year 2014 Publication Journal of magnetism and magnetic materials Abbreviated Journal (down) J Magn Magn Mater
Volume 349 Issue Pages 128-134
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We provide experimental evidence for the existence of ferromagnetism in bilayers of Pd/C-60 which is supported by theoretical calculations based on density functional theory (DFT). The observed ferromagnetism is surprising as C-60 and Pd films are both non-ferromagnetic in the non-interacting limit. Magnetization (M) versus applied field (H) data acquired at different temperatures (T) show magnetic hysteresis with typical coercive fields (H-c) on the order of 50 Oe. From the temperature-dependent magnetization M(T) we extract a Curie temperature (T-c >= 550 K) using Bloch-like power law extrapolations to high temperatures. Using DFT calculations we investigated all plausible scenarios for the interaction between the C-60 molecules and the Pd slabs, Pd single atoms and Pd clusters. DFT shows that while the C-60 molecules are nonmagnetic, Pd films have a degenerate ground state that subject to a weak perturbation, can become ferromagnetic. Calculations also show that the interaction of C-60 molecules with excess Pd atoms and with sharp edges of a Pd slab is the most likely configuration that render the system ferromagnetic Interestingly, the calculated charge transfer (0.016 e per surface Pd atom, 0.064 e per Pd for intimate contact region) between C-60 and Pd does not appear to play an important role. (C) 2013 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000326037600022 Publication Date 2013-08-02
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 2.63 Times cited 8 Open Access
Notes ; We thank Prof. Amlan Biswas and Daniel Grant for Atomic Force Microscopy measurements. This work is supported by the National Science Foundation (NSF) under Contract Number 1005301 (AFH). The authors also thank S. Ciraci for fruitful discussions. All the computational resources have been provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H. Sahin is also supported by a FWO Pegasus Marie Curie Long Fellowship during the study. ; Approved Most recent IF: 2.63; 2014 IF: 1.970
Call Number UA @ lucian @ c:irua:112214 Serial 1184
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Author Ozcan, M.; Ozen, S.; Yagmurcukardes, M.; Sahin, H.
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 (down) 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 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 Kandemir, A.; Peeters, F.M.; Sahin, H.
Title Monitoring the effect of asymmetrical vertical strain on Janus single layers of MoSSe via spectrum Type A1 Journal article
Year 2018 Publication The journal of chemical physics Abbreviated Journal (down) J Chem Phys
Volume 149 Issue 8 Pages 084707
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using first principles calculations, we study the structural and phononic properties of the recently synthesized Janus type single layers of molybdenum dichalcogenides. The Janus MoSSe single layer possesses 2H crystal structure with two different chalcogenide sides that lead to out-of-plane anisotropy. By virtue of the asymmetric structure of the ultra-thin Janus type crystal, we induced the out-of-plane anisotropy to show the distinctive vertical pressure effect on the vibrational properties of the Janus material. It is proposed that for the corresponding Raman active optical mode of the Janus structure, the phase modulation and the magnitude ratio of the strained atom and its first neighbor atom adjust the distinctive change in the eigen-frequencies and Raman activity. Moreover, a strong variation in the Raman activity of the Janus structure is obtained under bivertical and univertical strains. Not only eigen-frequency shifts but also Raman activities of the optical modes of the Janus structure exhibit distinguishable features. This study reveals that the vertical anisotropic feature of the Janus structure under Raman measurement allows us to distinguish which side of the Janus crystal interacts with the externals (substrate, functional adlayers, or dopants). Published by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000444035800044 Publication Date 2018-08-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited 11 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 TUBITAK under Project No. 117F095. F.M.P. was supported by the FLAG-ERA-TRANS<INF>2D</INF>TMD. ; Approved Most recent IF: 2.965
Call Number UA @ lucian @ c:irua:153711UA @ admin @ c:irua:153711 Serial 5115
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Author Baskurt, M.; Yagmurcukardes, M.; Peeters, F.M.; Sahin, H.
Title Stable single-layers of calcium halides (CaX₂, X = F, Cl, Br, I) Type A1 Journal article
Year 2020 Publication Journal Of Chemical Physics Abbreviated Journal (down) J Chem Phys
Volume 152 Issue 16 Pages 164116-164118
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract By means of density functional theory based first-principles calculations, the structural, vibrational, and electronic properties of 1H- and 1T-phases of single-layer CaX2 (X = F, Cl, Br, or I) structures are investigated. Our results reveal that both the 1H- and 1T-phases are dynamically stable in terms of their phonon band dispersions with the latter being the energetically favorable phase for all single-layers. In both phases of single-layer CaX2 structures, significant phonon softening occurs as the atomic radius increases. In addition, each structural phase exhibits distinctive Raman active modes that enable one to characterize either the phase or the structure via Raman spectroscopy. The electronic band dispersions of single-layer CaX2 structures reveal that all structures are indirect bandgap insulators with a decrease in bandgaps from fluorite to iodide crystals. Furthermore, the calculated linear elastic constants, in-plane stiffness, and Poisson ratio indicate the ultra-soft nature of CaX2 single-layers, which is quite important for their nanoelastic applications. Overall, our study reveals that with their dynamically stable 1T- and 1H-phases, single-layers of CaX2 crystals can be alternative ultra-thin insulators.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000531819100001 Publication Date 2020-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.4 Times cited 14 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 Project No. 117F095. H.S. acknowledges support from the Turkish Academy of Sciences under the GEBIP program. M.Y. was supported by a postdoctoral fellowship from the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 4.4; 2020 IF: 2.965
Call Number UA @ admin @ c:irua:169543 Serial 6615
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Author Sen, H.S.; Sahin, H.; Peeters, F.M.; Durgun, E.
Title Monolayers of MoS2 as an oxidation protective nanocoating material Type A1 Journal article
Year 2014 Publication Journal of applied physics Abbreviated Journal (down) J Appl Phys
Volume 116 Issue 8 Pages 083508
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract First-principle calculations are employed to investigate the interaction of oxygen with ideal and defective MoS2 monolayers. Our calculations show that while oxygen atoms are strongly bound on top of sulfur atoms, the oxygen molecule only weakly interacts with the surface. The penetration of oxygen atoms and molecules through a defect-free MoS2 monolayer is prevented by a very high diffusion barrier indicating that MoS2 can serve as a protective layer for oxidation. The analysis is extended to WS2 and similar coating characteristics are obtained. Our calculations indicate that ideal and continuous MoS2 and WS2 monolayers can improve the oxidation and corrosion-resistance of the covered surface and can be considered as an efficient nanocoating material. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000342821600017 Publication Date 2014-08-27
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 2.068 Times cited 52 Open Access
Notes ; This work was supported by the bilateral project between TUBITAK (through Grant No. 113T050) and Flemish Science Foundation (FWO-Vl). The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). E.D. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. H.S. is supported by an FWO Pegasus-long Marie Curie Fellowship. ; Approved Most recent IF: 2.068; 2014 IF: 2.183
Call Number UA @ lucian @ c:irua:121101 Serial 2194
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Author Yagmurcukardes, M.; Sahin, H.; Kang, J.; Torun, E.; Peeters, F.M.; Senger, R.T.
Title Pentagonal monolayer crystals of carbon, boron nitride, and silver azide Type A1 Journal article
Year 2015 Publication Journal of applied physics Abbreviated Journal (down) 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 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
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Author Torun, E.; Sahin, H.; Cahangirov, S.; Rubio, A.; Peeters, F.M.
Title Anisotropic electronic, mechanical, and optical properties of monolayer WTe2 Type A1 Journal article
Year 2016 Publication Journal of applied physics Abbreviated Journal (down) J Appl Phys
Volume 119 Issue 7 Pages 074307
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using first-principles calculations, we investigate the electronic, mechanical, and optical properties of monolayer WTe2. Atomic structure and ground state properties of monolayer WTe2 (T-d phase) are anisotropic which are in contrast to similar monolayer crystals of transition metal dichalcogenides, such as MoS2, WS2, MoSe2, WSe2, and MoTe2, which crystallize in the H-phase. We find that the Poisson ratio and the in-plane stiffness is direction dependent due to the symmetry breaking induced by the dimerization of the W atoms along one of the lattice directions of the compound. Since the semimetallic behavior of the T-d phase originates from this W-W interaction (along the a crystallographic direction), tensile strain along the dimer direction leads to a semimetal to semiconductor transition after 1% strain. By solving the Bethe-Salpeter equation on top of single shot G(0)W(0) calculations, we predict that the absorption spectrum of T-d-WTe2 monolayer is strongly direction dependent and tunable by tensile strain. (C) 2016 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000375158000022 Publication Date 2016-02-19
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 2.068 Times cited 62 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-V1) 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. S.C. and A.R. acknowledge the financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, European Research Council (ERC-2010-AdG-267374), Spanish grant (FIS2013-46159-C3-1-P), Grupos Consolidados (IT578-13), and AFOSR Grant No. FA2386-15-1-0006 AOARD 144088, H2020-NMP-2014 project MOSTOPHOS, GA No. SEP-210187476, and COST Action MP1306 (EUSpec). S.C. acknowledges the support from The Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388. ; Approved Most recent IF: 2.068
Call Number UA @ lucian @ c:irua:144747 Serial 4640
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Author Zhang, S.; Sahin, H.; Torun, E.; Peeters, F.; Martien, D.; DaPron, T.; Dilley, N.; Newman, N.
Title Fundamental mechanisms responsible for the temperature coefficient of resonant frequency in microwave dielectric ceramics Type A1 Journal article
Year 2017 Publication Journal of the American Ceramic Society Abbreviated Journal (down) J Am Ceram Soc
Volume 100 Issue 100 Pages 1508-1516
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The temperature coefficient of resonant frequency ((f)) of a microwave resonator is determined by three materials parameters according to the following equation: (f)=-(1/2 (epsilon) + 1/2 + (L)), where (L), (epsilon), and are defined as the linear temperature coefficients of the lattice constant, dielectric constant, and magnetic permeability, respectively. We have experimentally determined each of these parameters for Ba(Zn1/3Ta2/3)O-3, 0.8 at.% Ni-doped Ba(Zn1/3Ta2/3)O-3, and Ba(Ni1/3Ta2/3)O-3 ceramics. These results, in combination with density functional theory calculations, have allowed us to develop a much improved understanding of the fundamental physical mechanisms responsible for the temperature coefficient of resonant frequency, (f).
Address
Corporate Author Thesis
Publisher Place of Publication Columbus, Ohio Editor
Language Wos 000399610800034 Publication Date 2017-02-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7820 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.841 Times cited 6 Open Access
Notes ; ; Approved Most recent IF: 2.841
Call Number UA @ lucian @ c:irua:143682 Serial 4597
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