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Author Lee, Y.; Forte, J.D.'arf S.; Chaves, A.; Kumar, A.; Tran, T.T.; Kim, Y.; Roy, S.; Taniguchi, T.; Watanabe, K.; Chernikov, A.; Jang, J.I.; Low, T.; Kim, J. url  doi
openurl 
  Title Boosting quantum yields in two-dimensional semiconductors via proximal metal plates Type A1 Journal article
  Year (down) 2021 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 12 Issue 1 Pages 7095  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The short exciton lifetime and strong exciton-exciton interaction in transition metal dichalcogenides limit the efficiency of exciton emission. Here, the authors show that exciton-exciton interaction in monolayer WS2 can be screened using proximal metal plates, leading to an improved quantum yield. Monolayer transition metal dichalcogenides (1L-TMDs) have tremendous potential as atomically thin, direct bandgap semiconductors that can be used as convenient building blocks for quantum photonic devices. However, the short exciton lifetime due to the defect traps and the strong exciton-exciton interaction in TMDs has significantly limited the efficiency of exciton emission from this class of materials. Here, we show that exciton-exciton interaction in 1L-WS2 can be effectively screened using an ultra-flat Au film substrate separated by multilayers of hexagonal boron nitride. Under this geometry, induced dipolar exciton-exciton interaction becomes quadrupole-quadrupole interaction because of effective image dipoles formed within the metal. The suppressed exciton-exciton interaction leads to a significantly improved quantum yield by an order of magnitude, which is also accompanied by a reduction in the exciton-exciton annihilation (EEA) rate, as confirmed by time-resolved optical measurements. A theoretical model accounting for the screening of the dipole-dipole interaction is in a good agreement with the dependence of EEA on exciton densities. Our results suggest that fundamental EEA processes in the TMD can be engineered through proximal metallic screening, which represents a practical approach towards high-efficiency 2D light emitters.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000728559600014 Publication Date 2021-12-07  
  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 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:184870 Serial 7566  
Permanent link to this record
 

 
Author Wang, F.; Wang, C.; Chaves, A.; Song, C.; Zhang, G.; Huang, S.; Lei, Y.; Xing, Q.; Mu, L.; Xie, Y.; Yan, H. doi  openurl
  Title Prediction of hyperbolic exciton-polaritons in monolayer black phosphorus Type A1 Journal article
  Year (down) 2021 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 12 Issue 1 Pages 5628  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Hyperbolic polaritons exhibit large photonic density of states and can be collimated in certain propagation directions. The majority of hyperbolic polaritons are sustained in man-made metamaterials. However, natural-occurring hyperbolic materials also exist. Particularly, natural in-plane hyperbolic polaritons in layered materials have been demonstrated in MoO3 and WTe2, which are based on phonon and plasmon resonances respectively. Here, by determining the anisotropic optical conductivity (dielectric function) through optical spectroscopy, we predict that monolayer black phosphorus naturally hosts hyperbolic exciton-polaritons due to the pronounced in-plane anisotropy and strong exciton resonances. We simultaneously observe a strong and sharp ground state exciton peak and weaker excited states in high quality monolayer samples in the reflection spectrum, which enables us to determine the exciton binding energy of similar to 452 meV. Our work provides another appealing platform for the in-plane natural hyperbolic polaritons, which is based on excitons rather than phonons or plasmons.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000698984500003 Publication Date 2021-10-12  
  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 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:191688 Serial 8404  
Permanent link to this record
 

 
Author Raymenants, E.; Bultynck, O.; Wan, D.; Devolder, T.; Garello, K.; Souriau, L.; Thiam, A.; Tsvetanova, D.; Canvel, Y.; Nikonov, D.E.; Young, I.A.; Heyns, M.; Sorée, B.; Asselberghs, I.; Radu, I.; Couet, S.; Nguyen, V.D. url  doi
openurl 
  Title Nanoscale domain wall devices with magnetic tunnel junction read and write Type A1 Journal article
  Year (down) 2021 Publication Nature Electronics Abbreviated Journal  
  Volume 4 Issue 6 Pages 392-398  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The manipulation of fast domain wall motion in magnetic nanostructures could form the basis of novel magnetic memory and logic devices. However, current approaches for reading and writing domain walls require external magnetic fields, or are based on conventional magnetic tunnel junctions (MTJs) that are not compatible with high-speed domain wall motion. Here we report domain wall devices based on perpendicular MTJs that offer electrical read and write, and fast domain wall motion via spin-orbit torque. The devices have a hybrid free layer design that consists of platinum/cobalt (Pt/Co) or a synthetic antiferromagnet (Pt/Co/Ru/Co) into the free layer of conventional MTJs. We show that our devices can achieve good tunnelling magnetoresistance readout and efficient spin-transfer torque writing that is comparable to current magnetic random-access memory technology, as well as domain wall depinning efficiency that is similar to stand-alone materials. We also show that a domain wall conduit based on a synthetic antiferromagnet offers the potential for reliable domain wall motion and faster write speed compared with a device based on Pt/Co. Domain wall devices based on perpendicular magnetic tunnel junctions with a hybrid free layer design can offer electrical read and write, and fast domain wall motion driven via spin-orbit torque.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000665011500005 Publication Date 2021-06-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2520-1131 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:179673 Serial 7003  
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Author Zou, Y.-C.; Mogg, L.; Clark, N.; Bacaksiz, C.; Milanovic, S.; Sreepal, V.; Hao, G.-P.; Wang, Y.-C.; Hopkinson, D.G.; Gorbachev, R.; Shaw, S.; Novoselov, K.S.; Raveendran-Nair, R.; Peeters, F.M.; Lozada-Hidalgo, M.; Haigh, S.J. url  doi
openurl 
  Title Ion exchange in atomically thin clays and micas Type A1 Journal article
  Year (down) 2021 Publication Nature Materials Abbreviated Journal Nat Mater  
  Volume 20 Issue 12 Pages 1677-1682  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The physical properties of clays and micas can be controlled by exchanging ions in the crystal lattice. Atomically thin materials can have superior properties in a range of membrane applications, yet the ion-exchange process itself remains largely unexplored in few-layer crystals. Here we use atomic-resolution scanning transmission electron microscopy to study the dynamics of ion exchange and reveal individual ion binding sites in atomically thin and artificially restacked clays and micas. We find that the ion diffusion coefficient for the interlayer space of atomically thin samples is up to 10(4) times larger than in bulk crystals and approaches its value in free water. Samples where no bulk exchange is expected display fast exchange at restacked interfaces, where the exchanged ions arrange in islands with dimensions controlled by the moire superlattice dimensions. We attribute the fast ion diffusion to enhanced interlayer expandability resulting from weaker interlayer binding forces in both atomically thin and restacked materials. This work provides atomic scale insights into ion diffusion in highly confined spaces and suggests strategies to design exfoliated clay membranes with enhanced performance. Layered clays are of interest for membranes and many other applications but their ion-exchange dynamics remain unexplored in atomically thin materials. Here, using electron microscopy, it is found that the ion diffusion for few-layer two-dimensional clays approaches that of free water and that superlattice cation islands can form in twisted and restacked materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000689664000001 Publication Date 2021-09-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1476-1122; 1476-4660 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 39.737 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 39.737  
  Call Number UA @ admin @ c:irua:181691 Serial 6999  
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Author Bafekry, A.; Faraji, M.; Ziabari, A.A.; Fadlallah, M.M.; Nguyen, C., V; Ghergherehchi, M.; Feghhi, S.A.H. url  doi
openurl 
  Title A van der Waals heterostructure of MoS₂/MoSi₂N₄ : a first-principles study Type A1 Journal article
  Year (down) 2021 Publication New Journal Of Chemistry Abbreviated Journal New J Chem  
  Volume 45 Issue 18 Pages 8291-8296  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by the successful preparation of MoSi2N4 monolayers in the last year [Y.-L. Hong et al., Science, 2020, 369, 670-674], we investigate the structural, electronic and optical properties of the MoS2/MoSi2N4 heterostructure (HTS). The phonon dispersion and the binding energy calculations refer to the stability of the HTS. The heterostructure has an indirect bandgap of 1.26 (1.84) eV using PBE (HSE06) which is smaller than the corresponding value of MoSi2N4 and MoS2 monolayers. We find that the work function of the MoS2/MoSi2N4 HTS is smaller than the corresponding value of its individual monolayers. The heterostructure structure can enhance the absorption of light spectra not only in the ultraviolet region but also in the visible region as compared to MoSi2N4 and MoS2 monolayers. The refractive index behaviour of the HTS can be described as the cumulative effect which is well described in terms of a combination of the individual effects (the refractive index of MoSi2N4 and MoS2 monolayers).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000642436200001 Publication Date 2021-03-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1144-0546 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.269 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.269  
  Call Number UA @ admin @ c:irua:178300 Serial 6964  
Permanent link to this record
 

 
Author Faraji, M.; Bafekry, A.; Gogova, D.; Hoat, D.M.; Ghergherehchi, M.; Chuong, N.V.; Feghhi, S.A.H. url  doi
openurl 
  Title Novel two-dimensional ZnO₂, CdO₂ and HgO₂ monolayers: a first-principles-based prediction Type A1 Journal article
  Year (down) 2021 Publication New Journal Of Chemistry Abbreviated Journal New J Chem  
  Volume 45 Issue Pages 9368-9374  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this paper, the existence of monolayers with the chemical formula XO2, where X = Zn, Cd, and Hg with hexagonal and tetragonal lattice structures is theoretically predicted by means of first principles calculations. Through cohesive energy calculation and phonon dispersion simulation, it has been proven that the two-dimensional XO2 monolayers proposed are energetically and dynamically stable suggesting their potential experimental realization. Our detailed study demonstrates that these novel newly predicted materials are half-metals and dilute magnetic semiconductors, and they exhibit magnetism in the ground state. The half-metallic character could find many applications in electronic and spintronic devices. Research into the magnetic properties revealed here can enrich theoretical knowledge in this area and provide more potential candidates for XO2 2D-based materials and van der Waals heterostructures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000645671700001 Publication Date 2021-04-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1144-0546 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.269 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.269  
  Call Number UA @ admin @ c:irua:178245 Serial 7006  
Permanent link to this record
 

 
Author Dubinina, T.; Maklakov, S.; Petrusevich, E.; Borisova, N.E.; Trashin, S.A.; De Wael, K.; Tomilova, L.G. url  doi
openurl 
  Title Photoactive layers for photovoltaics based on near-infrared absorbing aryl-substituted naphthalocyanine complexes : preparation and investigation of properties Type A1 Journal article
  Year (down) 2021 Publication New Journal Of Chemistry Abbreviated Journal New J Chem  
  Volume 45 Issue 32 Pages 14815-14821  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Photoactive layers based on aryl- and aryloxy-substituted naphthalocyanines and conductive polymer poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV) were prepared using the spin-coating technique and their conductivity was tested in dark and under illumination. For this purpose novel octa-2-naphthoxy-substituted naphthalocyanines were synthesized starting from 6,7-di(2-naphthoxy)naphthalene-2,3-dicarbonitrile. For those novel naphthalocyanine complexes, spectral and electrochemical data were measured and compared with corresponding ones for other aryl-substituted analogues. In comparison to the previously studied naphthalocyanines with alkyl- and phenyl- groups, the formal oxidation and reduction potentials were rather similar. All target complexes demonstrate intense near-infrared absorption at 760-790 nm, which is about 30 nm bathochromically shifted in thin films. The photo-resistive effect was found increasing from composites comprised of naphthoxy- to phenyl-substituted naphthalocyanines. This peculiarity was explained by using optical and atomic force microscopy in terms of different sizes of aggregates formed. The photo-response time for novel composited was approximately 3 s, which is about 20 times faster than measured previously for the films deposited via the drop-casting technique.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000680389800001 Publication Date 2021-07-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1144-0546 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 3.269 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.269  
  Call Number UA @ admin @ c:irua:179884 Serial 8379  
Permanent link to this record
 

 
Author Tiwari, S.; Van de Put, M.L.; Sorée, B.; Vandenberghe, W.G. url  doi
openurl 
  Title Magnetic order and critical temperature of substitutionally doped transition metal dichalcogenide monolayers Type A1 Journal article
  Year (down) 2021 Publication npj 2D Materials and Applications Abbreviated Journal  
  Volume 5 Issue 1 Pages 54  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations, we investigate the magnetic order in two-dimensional (2D) transition-metal-dichalcogenide (TMD) monolayers: MoS2, MoSe2, MoTe2, WSe2, and WS2 substitutionally doped with period four transition-metals (Ti, V, Cr, Mn, Fe, Co, Ni). We uncover five distinct magnetically ordered states among the 35 distinct TMD-dopant pairs: the non-magnetic (NM), the ferromagnetic with out-of-plane spin polarization (Z FM), the out-of-plane polarized clustered FMs (clustered Z FM), the in-plane polarized FMs (X-Y FM), and the anti-ferromagnetic (AFM) state. Ni and Ti dopants result in an NM state for all considered TMDs, while Cr dopants result in an anti-ferromagnetically ordered state for all the TMDs. Most remarkably, we find that Fe, Mn, Co, and V result in an FM ordered state for all the TMDs, except for MoTe2. Finally, we show that V-doped MoSe2 and WSe2, and Mn-doped MoS2, are the most suitable candidates for realizing a room-temperature FM at a 16-18% atomic substitution.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000650635200004 Publication Date 2021-05-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2397-7132 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:179063 Serial 7001  
Permanent link to this record
 

 
Author Shi, R.; Choudhuri, D.; Kashiwar, A.; Dasari, S.; Wang, Y.; Banerjee, R.; Banerjee, D. doi  openurl
  Title α phase growth and branching in titanium alloys Type A1 Journal article
  Year (down) 2021 Publication Philosophical magazine Abbreviated Journal Philos Mag  
  Volume Issue Pages  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The morphology and spatial distribution of alpha (α) precipitates have been mapped as a function of Mo content in Ti-Mo binary alloys employing a combinatorial approach. Heat-treatments were carried out on compositionally graded Ti-xMo samples processed using a rapid throughput laser engineered net shape (LENS) process. The composition space spans 1.5 at% to 6 at% Mo with ageing at 750°C, 650°C and 600°C following a β solution treatment. Three distinct regimes of α morphology and distribution were observed. These are colony-dominated microstructures originating from grain boundary α allotriomorphs, bundles of intragranular α laths, and homogeneously distributed individual fine-scale α laths. Branching of the α precipitates was observed in all these domains in a manner reminiscent of solid-state dendritic growth. The phenomenon is particularly apparent at low volume fractions of α. Similar features are present in a wide variety of alloy compositions. 3-dimensional features of such branched structures have been analysed. Simulation of the branching process by phase field methods incorporating anisotropy in the α/β interface energy and elasticity suggests that it can be initiated at growth ledges present at broad faces of the α laths, driven by the enhancement of the diffusion flux at these steps. The dependence of branching on various parameters such as supersaturation and diffusivity, and microstructural features like ledge height and distribution and the presence of adjacent α variants has been evaluated.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000722082700001 Publication Date 2021-11-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1478-6435 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 1.505 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 1.505  
  Call Number UA @ admin @ c:irua:183616 Serial 6849  
Permanent link to this record
 

 
Author Hasnat, A. pdf  doi
openurl 
  Title Performance optimization of the nano-sized pick-up loop of a dc-SQUID Type A1 Journal article
  Year (down) 2021 Publication Physica C-Superconductivity And Its Applications Abbreviated Journal Physica C  
  Volume 583 Issue Pages 1353852  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A flux transformer, consisting of a superconducting primary loop (pick-up loop) in series with a superconducting secondary loop on which measurement is done, is considered to optimize the approach and sensitivity of the Superconducting QUantum Interference Device (SQUID). Performance of such a pick-up loop placed above a magnetic particle is investigated using the numerical Ginzburg-Landau (GL) simulations. By solving 3D GL equations, static properties of the device such as the distribution of Cooper-pair density and the screening current in the secondary coil have been investigated as a function of the dimensions of the primary loop. Dynamic properties, such as current-voltage characteristics and flux-dependent critical current of the device have also been addressed, all leading to conclusion that smaller size pick-up loop is the first requirement for its optimal sensitivity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000636420000010 Publication Date 2021-03-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0921-4534 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.404 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 1.404  
  Call Number UA @ admin @ c:irua:177725 Serial 7008  
Permanent link to this record
 

 
Author Nguyen, D.K.; Hoat, D.M.; Bafekry, A.; Van On, V.; Rivas-Silva, J.F.; Naseri, M.; Cocoletzi, G.H. pdf  doi
openurl 
  Title Theoretical prediction of the PtOX (X = S and Se) monolayers as promising optoelectronic and thermoelectric 2D materials Type A1 Journal article
  Year (down) 2021 Publication Physica E-Low-Dimensional Systems & Nanostructures Abbreviated Journal Physica E  
  Volume 131 Issue Pages 114732  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract In this paper, two new monolayers, namely PtOS and PtOSe, are theoretically predicted using first-principles calculations. Structural, electronic, optical and thermoelectric properties are explored using full-potential linearized augmented plane-wave (FP-LAPW) method and the semiclassical Boltzmann transport theory. Predicted two-dimensional (2D) materials show good dynamical, thermodynamic and structural stability. Calculated electronic structures indicate the indirect gap semiconductor nature of the PtOS and PtOSe single layers with energy gap of 1.346(2.436) and 0.978(1.978) eV as calculated with the WC(HSE06) functional, respectively. Density of states spectra and valence charge distribution maps suggest a mix of covalent and ionic characters of the chemical bonds. 2D materials at hand exhibit good absorption property in the visible regime with coefficient value reaching the order of 105/cm, even much larger in the ultraviolet, suggesting the promising optoelectronic applicability. Finally, the thermoelectric parameters including electrical conductivity, thermal conductivity, Seebeck coefficient, power factor and figure of merit are determined and analyzed. Results indicate prospective thermoelectric performance of both considered single layers as demonstrated by large figure of merit close to unity. Our work introduces two new 2D multifunctional materials that may possess potential applications in the optoelectronic and thermoelectric nano-devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000647410700007 Publication Date 2021-03-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1386-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.221 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 2.221  
  Call Number UA @ admin @ c:irua:178346 Serial 7030  
Permanent link to this record
 

 
Author Bafekry, A.; Gogova, D.; M. Fadlallah, M.; V. Chuong, N.; Ghergherehchi, M.; Faraji, M.; Feghhi, S.A.H.; Oskoeian, M. url  doi
openurl 
  Title Electronic and optical properties of two-dimensional heterostructures and heterojunctions between doped-graphene and C- and N-containing materials Type A1 Journal article
  Year (down) 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 8 Pages 4865-4873  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electronic and optical properties of vertical heterostructures (HTSs) and lateral heterojunctions (HTJs) between (B,N)-codoped graphene (dop@Gr) and graphene (Gr), C3N, BC3 and h-BN monolayers are investigated using van der Waals density functional theory calculations. We have found that all the considered HTSs are energetically and thermally feasible at room temperature, and therefore they can be synthesized experimentally. The dop@Gr/Gr, BC3/dop@Gr and BN/dop@Gr HTSs are semiconductors with direct bandgaps of 0.1 eV, 80 meV and 1.23 eV, respectively, while the C3N/dop@Gr is a metal because of the strong interaction between dop@Gr and C3N layers. On the other hand, the dop@Gr-Gr and BN-dop@Gr HTJs are semiconductors, whereas the C3N-dop@Gr and BC3-dop@Gr HTJs are metals. The proposed HTSs can enhance the absorption of light in the whole wavelength range as compared to Gr and BN monolayers. The applied electric field or pressure strain changes the bandgaps of the HTSs and HTJs, indicating that these HTSs are highly promising for application in nanoscale multifunctional devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000625306100038 Publication Date 2021-02-05  
  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 OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:177659 Serial 6986  
Permanent link to this record
 

 
Author Bafekry, A.; Yagmurcukardes, M.; Akgenc, B.; Ghergherehchi, M.; Mortazavi, B. url  doi
openurl 
  Title First-principles investigation of electronic, mechanical and thermoelectric properties of graphene-like XBi (X = Si, Ge, Sn) monolayers Type A1 Journal article
  Year (down) 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 21 Pages 12471-12478  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Research progress on single layer group III monochalcogenides has been increasing rapidly owing to their interesting physics. Herein, we investigate the dynamically stable single layer forms of XBi (X = Ge, Si or Sn) using density functional theory calculations. Phonon band dispersion calculations and ab initio molecular dynamics simulations reveal the dynamical and thermal stability of the considered monolayers. Raman spectra calculations indicate the existence of 5 Raman active phonon modes, 3 of which are prominent and can be observed in possible Raman measurements. The electronic band structures of the XBi single layers were investigated with and without the effects of spin-orbit coupling (SOC). Our results show that XBi single layers show semiconducting properties with narrow band gap values without SOC. However, only single layer SiBi is an indirect band gap semiconductor, while GeBi and SnBi exhibit metallic behaviors when adding spin-orbit coupling effects. In addition, the calculated linear elastic parameters indicate the soft nature of the predicted monolayers. Moreover, our predictions for the thermoelectric properties of single layer XBi reveal that SiBi is a good thermoelectric material with increasing temperature. Overall, it is proposed that single layer XBi structures can be alternative, stable 2D single layers with varying electronic and thermoelectric properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000653851100001 Publication Date 2021-04-08  
  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 OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:179007 Serial 6992  
Permanent link to this record
 

 
Author Bafekry, A.; Faraji, M.; Fadlallah, M.M.; Jappor, H.R.; Karbasizadeh, S.; Ghergherehchi, M.; Sarsari, I.A.; Ziabari, A.A. url  doi
openurl 
  Title Novel two-dimensional AlSb and InSb monolayers with a double-layer honeycomb structure : a first-principles study Type A1 Journal article
  Year (down) 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 34 Pages 18752-18759  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this work, motivated by the fabrication of an AlSb monolayer, we have focused on the electronic, mechanical and optical properties of AlSb and InSb monolayers with double-layer honeycomb structures, employing the density functional theory approach. The phonon band structure and cohesive energy confirm the stability of the XSb (X = Al and In) monolayers. The mechanical properties reveal that the XSb monolayers have a brittle nature. Using the GGA + SOC (HSE + SOC) functionals, the bandgap of the AlSb monolayer is predicted to be direct, while InSb has a metallic character using both functionals. We find that XSb (X = Al, In) two-dimensional bodies can absorb ultraviolet light. The present findings suggest several applications of AlSb and InSb monolayers in novel optical and electronic usages.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000686236800001 Publication Date 2021-08-05  
  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 OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:181712 Serial 7005  
Permanent link to this record
 

 
Author Faraji, M.; Bafekry, A.; Fadlallah, M.M.; Molaei, F.; Hieu, N.N.; Qian, P.; Ghergherehchi, M.; Gogova, D. url  doi
openurl 
  Title Surface modification of titanium carbide MXene monolayers (Ti₂C and Ti₃C₂) via chalcogenide and halogenide atoms Type A1 Journal article
  Year (down) 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 28 Pages 15319-15328  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Inspired by the recent successful growth of Ti2C and Ti3C2 monolayers, here, we investigate the structural, electronic, and mechanical properties of functionalized Ti2C and Ti3C2 monolayers by means of density functional theory calculations. The results reveal that monolayers of Ti2C and Ti3C2 are dynamically stable metals. Phonon band dispersion calculations demonstrate that two-surface functionalization of Ti2C and Ti(3)C(2)via chalcogenides (S, Se, and Te), halides (F, Cl, Br, and I), and oxygen atoms results in dynamically stable novel functionalized monolayer materials. Electronic band dispersions and density of states calculations reveal that all functionalized monolayer structures preserve the metallic nature of both Ti2C and Ti3C2 except Ti2C-O-2, which possesses the behavior of an indirect semiconductor via full-surface oxygen passivation. In addition, it is shown that although halide passivated Ti3C2 structures are still metallic, there exist multiple Dirac-like cones around the Fermi energy level, which indicates that semi-metallic behavior can be obtained upon external effects by tuning the energy of the Dirac cones. In addition, the computed linear-elastic parameters prove that functionalization is a powerful tool in tuning the mechanical properties of stiff monolayers of bare Ti2C and Ti3C2. Our study discloses that the electronic and structural properties of Ti2C and Ti3C2 MXene monolayers are suitable for surface modification, which is highly desirable for material property engineering and device integration.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000672406800001 Publication Date 2021-06-23  
  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 OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:179809 Serial 7027  
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Author Naseri, M.; Bafekry, A.; Faraji, M.; Hoat, D.M.; Fadlallah, M.M.; Ghergherehchi, M.; Sabbaghi, N.; Gogova, D. doi  openurl
  Title Two-dimensional buckled tetragonal cadmium chalcogenides including CdS, CdSe, and CdTe monolayers as photo-catalysts for water splitting Type A1 Journal article
  Year (down) 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 21 Pages 12226-12232  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Pure hydrogen production via water splitting is an ideal strategy for producing clean and sustainable energy. Two-dimensional (2D) cadmium chalcogenide single-layers with a tetragonal crystal structure, namely Tetra-CdX (X = S, Se, and Te) monolayers, are theoretically predicted by means of density functional theory (DFT). Their structural stability and electronic and optical properties are investigated. We find that Tetra-CdX single-layers are thermodynamically stable. Their stability decreases as we go down the 6A group in the periodic table, i.e., from X = S to Se, and Te which also means that the electronegativity decreases. All considered novel monolayers are indirect band gap semiconductors. Using the HSE06 functional the electronic band gaps of CdS, CdSe, and CdTe monolayers are predicted to be 3.10 eV, 2.97 eV, and 2.90 eV, respectively. The impact of mechanical strain on the physical properties was studied, which indicates that compressive strain increases the band gap and tensile strain decreases the band gap. The optical properties of the Tetra-CdX monolayers show the ability of these monolayers to absorb visible light. Due to the suitable band gaps and band edge positions of Tetra-CdX, these newly discovered 2D materials are promising for photocatalytic water splitting.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000651904600001 Publication Date 2021-04-30  
  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 4.123 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:178378 Serial 7041  
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Author Bafekry, A.; Karbasizadeh, S.; Stampfl, C.; Faraji, M.; Hoat, D.M.; Sarsari, I.A.; Feghhi, S.A.H.; Ghergherehchi, M. url  doi
openurl 
  Title Two-dimensional Janus semiconductor BiTeCl and BiTeBr monolayers : a first-principles study on their tunable electronic properties via an electric field and mechanical strain Type A1 Journal article
  Year (down) 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 28 Pages 15216-15223  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by the recent successful synthesis of highly crystalline ultrathin BiTeCl and BiTeBr layered sheets [Debarati Hajra et al., ACS Nano, 2020, 14, 15626], herein for the first time, we carry out a comprehensive study on the structural and electronic properties of BiTeCl and BiTeBr Janus monolayers using density functional theory (DFT) calculations. Different structural and electronic parameters including the lattice constant, bond lengths, layer thickness in the z-direction, different interatomic angles, work function, charge density difference, cohesive energy and Rashba coefficients are determined to acquire a deep understanding of these monolayers. The calculations show good stability of the studied single layers. BiTeCl and BiTeBr monolayers are semiconductors with electronic bandgaps of 0.83 and 0.80 eV, respectively. The results also show that the semiconductor-metal transformation can be induced by increasing the number of layers. In addition, the engineering of the electronic structure is also studied by applying an electric field, and mechanical uniaxial and biaxial strain. The results show a significant change of the bandgaps and that an indirect-direct band-gap transition can be induced. This study highlights the positive prospect for the application of BiTeCl and BiTeBr layered sheets in novel electronic and energy conversion systems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000670553900001 Publication Date 2021-06-16  
  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 OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:179827 Serial 7042  
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Author Sozen, Y.; Yagmurcukardes, M.; Sahin, H. doi  openurl
  Title Vibrational and optical identification of GeO₂ and GeO single layers : a first-principles study Type A1 Journal article
  Year (down) 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal 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 Vermeyen, T.; Brence, J.; Van Echelpoel, R.; Aerts, R.; Acke, G.; Bultinck, P.; Herrebout, W. url  doi
openurl 
  Title Exploring machine learning methods for absolute configuration determination with vibrational circular dichroism Type A1 Journal article
  Year (down) 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 35 Pages 19781-19789  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Molecular Spectroscopy (MolSpec)  
  Abstract The added value of supervised Machine Learning (ML) methods to determine the Absolute Configuration (AC) of compounds from their Vibrational Circular Dichroism (VCD) spectra was explored. Among all ML methods considered, Random Forest (RF) and Feedforward Neural Network (FNN) yield the best performance for identification of the AC. At its best, FNN allows near-perfect AC determination, with accuracy of prediction up to 0.995, while RF combines good predictive accuracy (up to 0.940) with the ability to identify the spectral areas important for the identification of the AC. No loss in performance of either model is observed as long as the spectral sampling interval used does not exceed the spectral bandwidth. Increasing the sampling interval proves to be the best method to lower the dimensionality of the input data, thereby decreasing the computational cost associated with the training of the models.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000691366500001 Publication Date 2021-08-25  
  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 OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:180290 Serial 7951  
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Author Yin, L.; Juneja, R.; Lindsay, L.; Pandey, T.; Parker, D.S. doi  openurl
  Title Semihard iron-based permanent-magnet materials Type A1 Journal article
  Year (down) 2021 Publication Physical Review Applied Abbreviated Journal Phys Rev Appl  
  Volume 15 Issue 2 Pages 024012  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Permanent magnets generally require a favorable, but difficult-to-achieve combination of high magnetization, Curie point, and magnetic anisotropy. Thus there have been few, if any, viable permanent magnets developed since the 1982 discovery of Nd2Fe14B [M. Sagawa, S. Fujimura, H. Yamamoto, Y. Matsuura, and S. Hirosawa, J. Appl. Phys. 57, 4094 (1985)]. Here we point out, both by direct first-principles calculations on the iron carbides and silicides Fe5C2, Fe5SiC, and Fe7C3 as well as a discussion of recent experimental findings, that there are numerous rare-earth-free iron-rich potential permanent-magnet materials with sufficient intrinsic magnetic properties to reasonably achieve room-temperature energy products of 20-25 MG Oe. This is substantially better than the performance of the best available rare-earth-free magnets based on ferrite, as well as shape-anisotropy-employing alnico. These magnets could plausibly fill, at low cost, the present performance “gap” [J. M. D. Coey, Scr. Mater. 67, 524 (2012)] between the best rare-earth-free magnets and rare-earth magnets such as Nd2Fe14B and Sm-Co.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000614707800002 Publication Date 2021-02-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2331-7019 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.808 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 4.808  
  Call Number UA @ admin @ c:irua:176624 Serial 6734  
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Author Sethu, K.K.V.; Ghosh, S.; Couet, S.; Swerts, J.; Sorée, B.; De Boeck, J.; Kar, G.S.; Garello, K. doi  openurl
  Title Optimization of tungsten beta-phase window for spin-orbit-torque magnetic random-access memory Type A1 Journal article
  Year (down) 2021 Publication Physical Review Applied Abbreviated Journal Phys Rev Appl  
  Volume 16 Issue 6 Pages 064009  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Switching induced by spin-orbit torque (SOT) is being vigorously explored, as it allows the control of magnetization using an in-plane current, which enables a three-terminal magnetic-tunnel-junction geometry with isolated read and write paths. This significantly improves the device endurance and the read stability, and allows reliable subnanosecond switching. Tungsten in the beta phase, beta-W, has the largest reported antidamping SOT charge-to-spin conversion ratio (theta(AD) approximate to -60%) for heavy metals. However, beta-W has a limitation when one is aiming for reliable technology integration: the beta phase is limited to a thickness of a few nanometers and enters the alpha phase above 4 nm in our samples when industry-relevant deposition tools are used. Here, we report our approach to extending the range of beta-W, while simultaneously improving the SOT efficiency by introducing N and O doping of W. Resistivity and XRD measurements confirm the extension of the beta phase from 4 nm to more than 10 nm, and transport characterization shows an effective SOT efficiency larger than -44.4% (reaching approximately -60% for the bulk contribution). In addition, we demonstrate the possibility of controlling and enhancing the perpendicular magnetic anisotropy of a storage layer (Co-Fe-B). Further, we integrate the optimized W(O, N) into SOT magnetic random-access memory (SOT-MRAM) devices and project that, for the same thickness of SOT material, the switching current decreases by 25% in optimized W(O, N) compared with our standard W. Our results open the path to using and further optimizing W for integration of SOT-MRAM technology.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000729005800002 Publication Date 2021-12-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2331-7019 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.808 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 4.808  
  Call Number UA @ admin @ c:irua:184832 Serial 7007  
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Author Vanderveken, F.; Mulkers, J.; Leliaert, J.; Van Waeyenberge, B.; Sorée, B.; Zografos, O.; Ciubotaru, F.; Adelmann, C. pdf  url
doi  openurl
  Title Confined magnetoelastic waves in thin waveguides Type A1 Journal article
  Year (down) 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 103 Issue 5 Pages 054439  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The characteristics of confined magnetoelastic waves in nanoscale ferromagnetic magnetostrictive waveguides have been investigated by a combination of analytical and numerical calculations. The presence of both magnetostriction and inverse magnetostriction leads to the coupling between confined spin waves and elastic Lamb waves. Numerical simulations of the coupled system have been used to extract the dispersion relations of the magnetoelastic waves as well as their mode profiles.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000627548800003 Publication Date 2021-02-26  
  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 3.836 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:177607 Serial 6976  
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Author van Duijn, F.; Osca, J.; Sorée, B. url  doi
openurl 
  Title Skyrmion elongation, duplication, and rotation by spin-transfer torque under spatially varying spin current Type A1 Journal article
  Year (down) 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 104 Issue 9 Pages 094426  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The effect of the spatially varying spin current on a skyrmion is numerically investigated. It is shown that an inhomogeneous current density induces an elongation of the skyrmion. This elongation can be controlled using current pulses of different strength and duration. Long current pulses lead to a splitting that forms two replicas of the initial skyrmion while for short pulses the elongated skyrmion relaxes back to its initial circular state through rotation in the MHz-GHz frequency range. The frequency is dependent on the strength of the damping coefficient.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000704236000002 Publication Date 2021-09-21  
  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 3.836 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:182467 Serial 7018  
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Author Demiroglu, I.; Sevik, C. url  doi
openurl 
  Title Extraordinary negative thermal expansion of two-dimensional nitrides : a comparative ab initio study of quasiharmonic approximation and molecular dynamics simulations Type A1 Journal article
  Year (down) 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 103 Issue 8 Pages 085430  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Thermal expansion behavior of two-dimensional (2D) nitrides and graphene were studied by ab initio molecular dynamics (MD) simulations as well as quasiharmonic approximation (QHA). Anharmonicity of the acoustic phonon modes are related to the unusual negative thermal expansion (NTE) behavior of the nitrides. Our results also hint that direct ab initio MD simulations are a more elaborate method to investigate thermal expansion behavior of 2D materials than the QHA. Nevertheless, giant NTE coefficients are found for h-GaN and h-AlN within the covered temperature range 100-600 K regardless of the chosen computational method. This unusual NTE of 2D nitrides is reasoned with the out-of-plane oscillations related to the rippling behavior of the monolayers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000620346100007 Publication Date 2021-02-22  
  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 3.836 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:176671 Serial 7956  
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Author Chaves, A.; Sousa, G.O.; Khaliji, K.; da Costa, D.R.; Farias, G.A.; Low, T. url  doi
openurl 
  Title Signatures of subband excitons in few-layer black phosphorus Type A1 Journal article
  Year (down) 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 103 Issue 16 Pages 165428  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Recent experimental measurements of light absorption in few-layer black phosphorus (BP) revealed a series of high and sharp peaks, interspersed by pairs of lower and broader features. Here, we propose a theoretical model for these excitonic states in few-layer BP within a continuum approach for the in-plane degrees of freedom and a tight-binding approximation that accounts for interlayer couplings. This yields excitonic transitions between different combinations of the subbands created by the coupled BP layers, which leads to a series of high and low oscillator strength excitonic states, consistent with the experimentally observed bright and dark exciton peaks, respectively. The main characteristics of such subband exciton states, as well as the possibility to control their energies and oscillator strengths via applied electric and magnetic fields, are discussed, towards a full understanding of the excitonic spectrum of few-layer BP and its tunability.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000647175200002 Publication Date 2021-04-28  
  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 3.836 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:178384 Serial 8523  
Permanent link to this record
 

 
Author Shi, W.; Pandey, T.; Lindsay, L.; Woods, L.M. doi  openurl
  Title Vibrational properties and thermal transport in quaternary chalcogenides : the case of Te-based compositions Type A1 Journal article
  Year (down) 2021 Publication Physical review materials Abbreviated Journal  
  Volume 5 Issue 4 Pages 045401  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Vibrational thermal properties of CuZn2InTe4, AgZn2InTe4, and Cu2CdSnTe4, derived from binary II-VI zinc-blendes, are reported based on first-principles calculations. While the chalcogenide atoms in these materials have the same lattice positions, the cation atom arrangements vary, resulting in different crystal symmetries and subsequent properties. The compositional differences have important effects on the vibrational thermal characteristics of the studied materials, which demonstrate that low-frequency optical phonons hybridize with acoustic phonons and lead to enhanced phonon-phonon scattering and low lattice thermal conductivities. The phonon density of states, mode Gruneisen parameters, and phonon scattering rates are also calculated, enabling deeper insight into the microscopic thermal conduction processes in these materials. Compositional variations drive differences among the three materials considered here; nonetheless, their structural similarities and generally low thermal conductivities (0.5-4 W/mK at room temperature) suggest that other similar II-VI zinc-blende derived materials will also exhibit similarly low values, as also corroborated by experimental data. This, combined with the versatility in designing a variety of motifs on the overall structure, makes quaternary chalcogenides interesting for thermal management and energy conversion applications that require low thermal conductivity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000655931400005 Publication Date 2021-04-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:179140 Serial 7045  
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Author Tiwari, S.; Vanherck, J.; Van de Put, M.L.; Vandenberghe, W.G.; Sorée, B. url  doi
openurl 
  Title Computing Curie temperature of two-dimensional ferromagnets in the presence of exchange anisotropy Type A1 Journal article
  Year (down) 2021 Publication Physical review research Abbreviated Journal  
  Volume 3 Issue 4 Pages 043024  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We compare three first-principles methods of calculating the Curie temperature in two-dimensional (2D) ferromagnetic materials (FM), modeled using the Heisenberg model, and propose a simple formula for estimating the Curie temperature with high accuracy that works for all common 2D lattice types. First, we study the effect of exchange anisotropy on the Curie temperature calculated using the Monte Carlo (MC), the Green's function, and the renormalized spin-wave (RNSW) methods. We find that the Green's function method overestimates the Curie temperature in high-anisotropy regimes compared to the MC method, whereas the RNSW method underestimates the Curie temperature compared to the MC and the Green's function methods. Next, we propose a closed-form formula for calculating the Curie temperature of 2D FMs, which provides an estimate of the Curie temperature that is greatly improved over the mean-field expression for magnetic material screening. We apply the closed-form formula to predict the Curie temperature 2D magnets screened from the C2DB database and discover several high Curie temperature FMs, with Fe2F2 and MoI2 emerging as the most promising 2D ferromagnets. Finally, by comparing to experimental results for CrI3, CrCl3, and CrBr3, we conclude that for small effective anisotropies, the Green's-function-based equations are preferable, while for larger anisotropies, MC-based results are more predictive.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000707506500001 Publication Date 2021-10-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:182522 Serial 6975  
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Author Aucar Boidi, N.; Fernández García, H.; Nunez-Fernandez, Y.; Hallberg, K. url  doi
openurl 
  Title In-gap band in the one-dimensional two-orbital Kanamori-Hubbard model with interorbital Coulomb interaction Type A1 Journal article
  Year (down) 2021 Publication Physical review research Abbreviated Journal  
  Volume 3 Issue 4 Pages 043213  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp X-ray Imaging and Spectroscopy (AXIS)  
  Abstract We study the electronic spectral properties at zero temperature of the one-dimensional (1D) version of the degenerate two-orbital Kanamori-Hubbard model, one of the well-established frameworks to study transition metal compounds, using state-of-the-art numerical techniques based on the density matrix renormalization group. While the system is Mott insulating for the half-filled case, as expected for an interacting 1D system, we find interesting and rich structures in the single-particle density of states (DOS) for the hole-doped system. In particular, we find the existence of in-gap states which are pulled down to lower energies from the upper Hubbard band with increasing the interorbital Coulomb interaction V. We analyze the composition of the DOS by projecting it onto different local excitations, and we observe that for large dopings these in-gap excitations are formed mainly by interorbital holon-doublon (HD) states and their energies follow approximately the HD states in the atomic limit. We observe that the Hund interaction J increases the width of the in-gap band, as expected from the two-particle fluctuations in the Hamiltonian. The observation of a finite density of states within the gap between the Hubbard bands for this extended 1D model indicates that these systems present a rich excitation spectra which could help us understand the microscopic physics behind multiorbital compounds.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000736651500002 Publication Date 2021-12-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:184836 Serial 8073  
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Author Liang, Y.-S.; Xue, C.; Zhang, Y.-R.; Wang, Y.-N. doi  openurl
  Title Investigation of active species in low-pressure capacitively coupled N-2/Ar plasmas Type A1 Journal article
  Year (down) 2021 Publication Physics Of Plasmas Abbreviated Journal Phys Plasmas  
  Volume 28 Issue 1 Pages 013510  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract In this paper, a self-consistent fluid model is developed focusing on the plasma parameters in capacitively coupled 20% N 2-80% Ar discharges. Measurements of ion density are performed with the help of a floating double probe, and the emission intensities from Ar(4p) and N 2 ( B ) transitions are detected by an optical emission spectroscopy to estimate their relative densities. The consistency between the numerical and experimental results confirms the reliability of the simulation. Then the plasma characteristics, specifically the reaction mechanisms of active species, are analyzed under various voltages. The increasing voltage leads to a monotonous increase in species density, whereas a less homogeneous radial distribution is observed at a higher voltage. Due to the high concentration of Ar gas, Ar + becomes the main ion, followed by the N 2 +</mml:msubsup> ion. Besides the electron impact ionization of neutrals, the charge transfer processes of Ar +/ N 2 and N 2 +</mml:msubsup>/Ar are found to have an impact on the ionic species. The results indicate that adopting the lower charge transfer reaction rate coefficients weakens the Ar + ion density and yields a higher N 2 +</mml:msubsup> ion density. However, the effect on the species spatial distributions and other species densities is limited. As for the excited-state species, the electron impact excitation of background gases remains overwhelming in the formation of Ar(4p), N 2 ( B ), and N 2 ( a ' ), whereas the <mml:msub> N 2 ( A ) molecules are mainly formed by the decay of <mml:msub> N 2 ( B ). In addition, the dissociation of <mml:msub> N 2 collided by excited-state Ar atoms dominates the N generation, which are mostly depleted to produce N + ions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000629931300002 Publication Date 2021-01-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1070-664x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.115 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 2.115  
  Call Number UA @ admin @ c:irua:177669 Serial 6767  
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Author Xiaoyan, S.; Zhang, Y.-R.; Wang, Y.-N.; He, J.-X. doi  openurl
  Title Fluid simulation of the superimposed dual-frequency source effect in inductively coupled discharges Type A1 Journal article
  Year (down) 2021 Publication Physics Of Plasmas Abbreviated Journal Phys Plasmas  
  Volume 28 Issue 11 Pages 113504-113510  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Superimposition of dual frequencies (DFs) is one of the methods used for controlling plasma distribution in an inductively coupled plasma (ICP) source. The effects of a superimposed DF on the argon plasma characteristics have been investigated using a two-dimensional self-consistent fluid model. When both currents are fixed at 6A, the plasma density drops with decrease in one of the source frequencies due to less efficient heating and the plasma uniformity improves significantly. Moreover, for ICP operated with superimposed DFs (i.e., 4.52MHz/13.56MHz and 2.26MHz/13.56MHz), the current source exhibits the same period as the low frequency (LF) component, and the plasma density is higher than that obtained at a single frequency (i.e., 4.52 and 2.26MHz) with the same total current of 12A. However, at superimposed current frequencies of 6.78MHz/13.56MHz, the plasma density is lower than that obtained at a single frequency of 6.78MHz due to the weaker negative azimuthal electric field between two positive maxima during one period of 6.78MHz. When the superimposed DF ICP operates at 2.26 and 13.56MHz, the rapid oscillations of the induced electric field become weaker during one period of 2.26MHz as the current ratio of 2.26MHz/13.56MHz rises from 24A/7 A to 30A/1 A, and the plasma density drops with the current ratio due to weakened electron heating. The uniformity of plasma increases due to sufficient diffusion under the low-density condition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000760326100004 Publication Date 2021-11-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1070-664x ISBN Additional Links UA library record; WoS full record  
  Impact Factor 2.115 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 2.115  
  Call Number UA @ admin @ c:irua:187245 Serial 7974  
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