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Author Matulis, A.; Zarenia, M.; Peeters, F.M. pdf  doi
openurl 
  Title Wave fronts and packets in 1D models of different meta-materials : graphene, left-handed media and transmission line Type A1 Journal article
  Year 2015 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B  
  Volume 252 Issue 252 Pages 2330-2338  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A comparative study is made of the propagation of wave packets and fronts in three different meta-media, i.e. graphene, left-handed media (LHM) and transmission lines, using one-dimensional models. It is shown that a potential step in graphene influences only the frequency of the electronic wave, i.e., the particular spectrum branch (electron or hole) to which the wave belongs to, while the envelop function (the wave front or packet form) remains unchanged. Although the model for a vacuum and LHM interface is similar to that of the potential step in graphene, the solutions are quite different due to differences in the chirality of the waves. Comparing the propagation of wave fronts and packets in a standard transmission line and its meta-analog we demonstrate that the propagating packets in the meta-line are much more deformed as compared to the standard one, including broadening, asymmetry and even the appearance of fast moving precursors. This influence is seen not only in the case of packets with steep fronts but in soft Gaussian packets as well.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000362722300025 Publication Date 2015-07-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-1972 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.674 Times cited 1 Open Access  
  Notes ; This work was financially supported by the Flemish Science Foundation (FWO-Vl), the Methusalem foundation of the Flemish government, and the European Social Fund under the Global Grant Measure (Grant No. VP1-3.1-SMM-07-K-02-046). ; Approved Most recent IF: 1.674; 2015 IF: 1.489  
  Call Number UA @ lucian @ c:irua:128776 Serial 4277  
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Author Singh, S.K.; Costamagna, S.; Neek-Amal, M.; Peeters, F.M. doi  openurl
  Title Melting of partially fluorinated graphene : from detachment of fluorine atoms to large defects and random coils Type A1 Journal article
  Year 2014 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 118 Issue 8 Pages 4460-4464  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The melting of fluorographene is very unusual and depends strongly on the degree of fluorination. For temperatures below 1000 K, fully fluorinated graphene (FFG) is thermomechanically more stable than graphene but at T-m approximate to 2800 K FFG transits to random coils which is almost 2 times lower than the melting temperature of graphene, i.e., 5300 K. For fluorinated graphene up to 30% ripples causes detachment of individual F-atoms around 2000 K, while for 40%-60% fluorination large defects are formed beyond 1500 K and beyond 60% of fluorination F-atoms remain bonded to graphene until melting. The results agree with recent experiments on the dependence of the reversibility of the fluorination process on the percentage of fluorination.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000332188100069 Publication Date 2014-01-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447; 1932-7455 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 16 Open Access  
  Notes ; This work was supported by the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-VI). Financial support from the Collaborative program MINCyT (Argentina)-FWO(Belgium) is also acknowledged. ; Approved Most recent IF: 4.536; 2014 IF: 4.772  
  Call Number UA @ lucian @ c:irua:128874 Serial 4600  
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Author Gillis, S.; Jaykka, J.; Milošević, M.V. url  doi
openurl 
  Title Vortex states in mesoscopic three-band superconductors Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 89 Issue 2 Pages 024512  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using multicomponent Ginzburg-Landau simulations, we show a plethora of vortex states possible in mesoscopic three-band superconductors. We find that mesoscopic confinement stabilizes chiral states, with nontrivial phase differences between the band condensates, as the ground state of the system. As a consequence, we report the broken-symmetry vortex states, the chiral states where vortex cores in different band condensates do not coincide (split-core vortices), as well as fractional-flux vortex states with broken time-reversal symmetry.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000333653800001 Publication Date 2014-01-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 26 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO). Critical remarks of Lucia Komendova are gratefully acknowledged. ; Approved Most recent IF: 3.836; 2014 IF: 3.736  
  Call Number UA @ lucian @ c:irua:128885 Serial 4611  
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Author Muñoz, W.A.; Covaci, L.; Peeters, F.M. pdf  url
doi  openurl
  Title Superconducting current and proximity effect in ABA and ABC multilayer graphene Josephson junctions Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 88 Pages 214502  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using a numerical tight-binding approach based on the Chebyshev–Bogoliubov–de Gennes method we describe Josephson junctions made of multilayer graphene contacted by top superconducting gates. Both Bernal (ABA) and rhombohedral (ABC) stacking are considered and we find that the type of stacking has a strong effect on the proximity effect and the supercurrent flow. For both cases the pair amplitude shows a polarization between dimer and nondimer atoms, being more pronounced for rhombohedral stacking. Even though the proximity effect in nondimer sites is enhanced when compared to single-layer graphene, we find that the supercurrent is suppressed. The spatial distribution of the supercurrent shows that for Bernal stacking the current flows only in the topmost layers while for rhombohedral stacking the current flows throughout the whole structure.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000328569900004 Publication Date 2013-12-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 4 Open Access  
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem funding of the Flemish Government Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number CMT @ cmt @ c:irua:128896 Serial 3962  
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Author Arsoski, V.; Tadic, M.; Peeters, F.M. doi  openurl
  Title Electric field tuning of the optical excitonic Aharonov-Bohm effect in nanodots grown by droplet epitaxy Type A1 Journal article
  Year 2013 Publication Physica scripta Abbreviated Journal Phys Scripta  
  Volume T157 Issue Pages 014002  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Neutral excitons in axially symmetric GaAs nanodots embedded in an (Al, Ga) As matrix, which are formed by the droplet epitaxy technique, are investigated theoretically. An electric field perpendicular to the nanodot base results in both a vertical and an in-plane exciton polarization, which is beneficial for the appearance of the excitonic Aharonov-Bohm effect. In the range of low magnetic fields (below 5 Tesla), we found that the bright and dark exciton states can cross twice. This results in oscillations of the photoluminescence intensity with magnetic field, which are a striking manifestation of the optical excitonic Aharonov-Bohm effect.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Stockholm Editor  
  Language Wos 000332504600003 Publication Date 2013-11-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-8949 ISBN Additional Links (up) UA library record; WoS full record  
  Impact Factor 1.28 Times cited Open Access  
  Notes ; This work was supported by the EU Network of Excellence: SANDiE, the Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 1.28; 2013 IF: 1.296  
  Call Number UA @ lucian @ c:irua:128901 Serial 4594  
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Author Muñoz, W.A.; Covaci, L.; Peeters, F.M. pdf  url
doi  openurl
  Title Disordered graphene Josephson junctions Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 91 Issue 91 Pages 054506  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A tight-binding approach based on the Chebyshev-Bogoliubov-de Gennes method is used to describe disordered single-layer graphene Josephson junctions. Scattering by vacancies, ripples, or charged impurities is included. We compute the Josephson current and investigate the nature of multiple Andreev reflections, which induce bound states appearing as peaks in the density of states for energies below the superconducting gap. In the presence of single-atom vacancies, we observe a strong suppression of the supercurrent, which is a consequence of strong intervalley scattering. Although lattice deformations should not induce intervalley scattering, we find that the supercurrent is still suppressed, which is due to the presence of pseudomagnetic barriers. For charged impurities, we consider two cases depending on whether the average doping is zero, i.e., existence of electron-hole puddles, or finite. In both cases, short-range impurities strongly affect the supercurrent, similar to the vacancies scenario.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000349436500001 Publication Date 2015-02-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 7 Open Access  
  Notes This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Methusalem funding of the Flemish Government. Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number c:irua:129192 Serial 3961  
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Author Arsoski, V.V.; Čukarić, N.A.; Tadic, M.Z.; Peeters, F.M. pdf  url
doi  openurl
  Title An efficient finite-difference scheme for computation of electron states in free-standing and core-shell quantum wires Type A1 Journal article
  Year 2015 Publication Computer physics communications Abbreviated Journal Comput Phys Commun  
  Volume 197 Issue 197 Pages 17-26  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electron states in axially symmetric quantum wires are computed by means of the effective-mass Schrodinger equation, which is written in cylindrical coordinates phi, rho, and z. We show that a direct discretization of the Schrodinger equation by central finite differences leads to a non-symmetric Hamiltonian matrix. Because diagonalization of such matrices is more complex it is advantageous to transform it in a symmetric form. This can be done by the Liouville-like transformation proposed by Rizea et al. (2008), which replaces the wave function psi(rho) with the function F(rho) = psi(rho)root rho and transforms the Hamiltonian accordingly. Even though a symmetric Hamiltonian matrix is produced by this procedure, the computed wave functions are found to be inaccurate near the origin, and the accuracy of the energy levels is not very high. In order to improve on this, we devised a finite-difference scheme which discretizes the Schrodinger equation in the first step, and then applies the Liouville-like transformation to the difference equation. Such a procedure gives a symmetric Hamiltonian matrix, resulting in an accuracy comparable to the one obtained with the finite element method. The superior efficiency of the new finite-difference scheme (FDM) is demonstrated for a few p-dependent one-dimensional potentials which are usually employed to model the electron states in free-standing and core shell quantum wires. The new scheme is compared with the other FDM schemes for solving the effective-mass Schrodinger equation, and is found to deliver energy levels with much smaller numerical error for all the analyzed potentials. It also gives more accurate results than the scheme of Rizea et al., except for the ground state of an infinite rectangular potential in freestanding quantum wires. Moreover, the PT symmetry is invoked to explain similarities and differences between the considered FDM schemes. (C) 2015 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000362919500003 Publication Date 2015-08-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0010-4655 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.936 Times cited 4 Open Access  
  Notes ; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia (project III 45003) and the Fonds Wetenschappelijk Onderzoek (Belgium). ; Approved Most recent IF: 3.936; 2015 IF: 3.112  
  Call Number UA @ lucian @ c:irua:129412 Serial 4139  
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Author Sobrino Fernandez, M.; Misko, V.R.; Peeters, F.M. url  doi
openurl 
  Title Self-assembly of Janus particles into helices with tunable pitch Type A1 Journal article
  Year 2015 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E  
  Volume 92 Issue 92 Pages 042309  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Janus particles present an important class of building blocks for directional assembly. These are compartmentalized colloids with two different hemispheres. In this work we consider a three-dimensional model of Janus spheres that contain one hydrophobic and one charged hemisphere. Using molecular dynamics simulations, we study the morphology of these particles when confined in a channel-like environment. The interplay between the attractive and repulsive forces on each particle gives rise to a rich phase space where the relative orientation of each particle plays a dominant role in the formation of large-scale clusters. The interest in this system is primarily due to the fact that it could give a better understanding of the mechanisms of the formation of polar membranes. A variety of ordered membranelike morphologies is found consisting of single and multiple connected chain configurations. The helicity of these chains can be chosen by simply changing the salt concentration of the solution. Special attention is given to the formation of Bernal spirals. These helices are composed of regular tetrahedra and are known to exhibit nontrivial translational and rotational symmetry.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication Melville, N.Y. Editor  
  Language Wos 000362903700004 Publication Date 2015-10-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1539-3755; 1550-2376 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.366 Times cited 18 Open Access  
  Notes ; This work was supported by the Fund for Scientific Research Flanders (FWO) and by the “Odysseus” program of the Flemish government and FWO. ; Approved Most recent IF: 2.366; 2015 IF: 2.288  
  Call Number UA @ lucian @ c:irua:129416 Serial 4241  
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Author Alyörük, M.M.; Aierken, Y.; Çakır, D.; Peeters, F.M.; Sevik, C. pdf  url
doi  openurl
  Title Promising Piezoelectric Performance of Single Layer Transition-Metal Dichalcogenides and Dioxides Type A1 Journal article
  Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 119 Issue 119 Pages 23231-23237  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Piezoelectricity is a unique material property that allows one to convert mechanical energy into electrical one or vice versa. Transition metal dichalcogenides (TMDC) and transition metal dioxides (TMDO) are expected to have great potential for piezoelectric device applications due to their noncentrosymmetric and two-dimensional crystal structure. A detailed theoretical investigation of the piezoelectric stress (e 11 ) and piezoelectric strain (d 11 ) coefficients of single layer TMDCs and TMDOs with chemical formula MX 2 (where M= Cr, Mo, W, Ti, Zr, Hf, Sn and X = O, S, Se, Te) is presented by using first-principles calculations based on density func- tional theory. We predict that not only the Mo- and W-based members of this family but also the other materials with M= Cr, Ti, Zr and Sn exhibit highly promising piezoelectric properties. CrTe 2 has the largest e 11 and d 11 coefficients among the group VI elements (i.e., Cr, Mo, and W). In addition, the relaxed-ion e 11 and d 11 coefficients of SnS 2 are almost the same as those of CrTe 2 . Furthermore, TiO 2 and ZrO 2 pose comparable or even larger e 11 coefficients as compared to Mo- and W-based TMDCs and TMDOs. Our calculations reveal that TMDC and TMDO structures are strong candidates for future atomically thin piezoelectric applications such as transducers, sensors, and energy harvesting devices due to their piezoelectric coefficients that are comparable (even larger) to currently used bulk piezoelectric materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000362702100054 Publication Date 2015-09-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 134 Open Access  
  Notes M.M.A and C.S. acknowledges the support from Scientific and Technological Research Council of Turkey (TUBITAK- 113F333). C.S. acknowledges support from Anadolu University (BAP-1407F335, -1505F200), and Turkish Academy of Sciences (TUBA-GEBIP). 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. Approved Most recent IF: 4.536; 2015 IF: 4.772  
  Call Number c:irua:129418 Serial 4035  
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Author Moors, K.; Sorée, B.; Magnus, W. url  doi
openurl 
  Title Modeling surface roughness scattering in metallic nanowires Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 118 Issue 118 Pages 124307  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Ando's model provides a rigorous quantum-mechanical framework for electron-surface roughness scattering, based on the detailed roughness structure. We apply this method to metallic nanowires and improve the model introducing surface roughness distribution functions on a finite domain with analytical expressions for the average surface roughness matrix elements. This approach is valid for any roughness size and extends beyond the commonly used Prange-Nee approximation. The resistivity scaling is obtained from the self-consistent relaxation time solution of the Boltzmann transport equation and is compared to Prange-Nee's approach and other known methods. The results show that a substantial drop in resistivity can be obtained for certain diameters by achieving a large momentum gap between Fermi level states with positive and negative momentum in the transport direction. (C) 2015 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000362565800032 Publication Date 2015-09-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 11 Open Access  
  Notes ; ; Approved Most recent IF: 2.068; 2015 IF: 2.183  
  Call Number UA @ lucian @ c:irua:129425 Serial 4207  
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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.; doi  openurl
  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 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 (up) 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 Neek-Amal, M; Peeters, F.M. url  doi
openurl 
  Title Partially hydrogenated and fluorinated graphene : structure, roughness, and negative thermal expansion Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 155430  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The structural properties of partially hydrogenated and fluorinated graphene with different percentages of H/F atoms are investigated using molecular dynamics simulations based on reactive force field (ReaxFF) potentials. We found that the roughness of graphene varies with the percentage (p) of H or F and in both cases is maximal around p = 50%. Similar results were obtained for partially oxidized graphene. The two-dimensional area size of partially fluorinated and hydrogenated graphene exhibits a local minimum around p = 35% coverage. The lattice thermal contraction in partially functionalized graphene is found to be one order of magnitude larger than that of fully covered graphene. We also show that the armchair structure for graphene oxide (similar to the structure of fully hydrogenated and fluorinated graphene) is unstable. Our results show that the structure of partially functionalized graphene changes nontrivially with the C : H and C : F ratio as well as with temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000363294100005 Publication Date 2015-10-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 5 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number UA @ lucian @ c:irua:129448 Serial 4221  
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Author Curran, P.J.; Desoky, W.M.; Milošević, M.V.; Chaves, A.; Laloe, J.-B.; Moodera, J.S.; Bending, S.J. url  doi
openurl 
  Title Spontaneous symmetry breaking in vortex systems with two repulsive lengthscales Type A1 Journal article
  Year 2015 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 5 Issue 5 Pages 15569  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Scanning Hall probe microscopy (SHPM) has been used to study vortex structures in thin epitaxial films of the superconductor MgB2. Unusual vortex patterns observed in MgB2 single crystals have previously been attributed to a competition between short-range repulsive and long-range attractive vortex-vortex interactions in this two band superconductor; the type 1.5 superconductivity scenario. Our films have much higher levels of disorder than bulk single crystals and therefore both superconducting condensates are expected to be pushed deep into the type 2 regime with purely repulsive vortex interactions. We observe broken symmetry vortex patterns at low fields in all samples after field-cooling from above T-c. These are consistent with those seen in systems with competing repulsions on disparate length scales, and remarkably similar structures are reproduced in dirty two band Ginzburg-Landau calculations, where the simulation parameters have been defined by experimental observations. This suggests that in our dirty MgB2 films, the symmetry of the vortex structures is broken by the presence of vortex repulsions with two different lengthscales, originating from the two distinct superconducting condensates. This represents an entirely new mechanism for spontaneous symmetry breaking in systems of superconducting vortices, with important implications for pinning phenomena and high current density applications.  
  Address  
  Corporate Author Thesis  
  Publisher Nature Publishing Group Place of Publication London Editor  
  Language Wos 000363306000002 Publication Date 2015-10-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.259 Times cited 12 Open Access  
  Notes ; P.J.C. and S.J.B. acknowledge support from EPSRC in the UK under grant number EP/J010626/1 and the NanoSC COST Action MP-1201. M.V.M. thanks the Research Foundation-Flanders (FWO) and CAPES Brazil. A.C. acknowledges the financial support of CNPq, under the PRONEX/FUNCAP and PQ programs. J.-B.L. and J.S.M. acknowledge ONR Grant N00014-06-01-0235. ; Approved Most recent IF: 4.259; 2015 IF: 5.578  
  Call Number UA @ lucian @ c:irua:129450 Serial 4248  
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Author Milovanović, S.P.; Moldovan, D.; Peeters, F.M. pdf  url
doi  openurl
  Title Veselago lensing in graphene with a p-n junction: Classical versus quantum effects Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 118 Issue 118 Pages 154308  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The feasibility of Veselago lensing in graphene with a p-n junction is investigated numerically for realistic injection leads. Two different set-ups with two narrow leads are considered with absorbing or reflecting side edges. This allows us to separately determine the influence of scattering on electron focusing for the edges and the p-n interface. Both semiclassical and tight-binding simulations show a distinctive peak in the transmission probability that is attributed to the Veselago lensing effect. We investigate the robustness of this peak on the width of the injector, the position of the p-n interface, and different gate potential profiles. Furthermore, the influence of scattering by both short- and long-range impurities is considered.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000363535800022 Publication Date 2015-10-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979;1089-7550; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 19 Open Access  
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. Approved Most recent IF: 2.068; 2015 IF: 2.183  
  Call Number c:irua:129452 Serial 3969  
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Author Çakir, D.; Peeters, F.M. pdf  url
doi  openurl
  Title Fluorographane : a promising material for bipolar doping of MoS2 Type A1 Journal article
  Year 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 17 Issue 17 Pages 27636-27641  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first principles calculations we investigate the structural and electronic properties of interfaces between fluorographane and MoS2. Unsymmetrical functionalization of graphene with H and F results in an intrinsic dipole moment perpendicular to the plane of the buckled graphene skeleton. Depending on the orientation of this dipole moment, the electronic properties of a physically absorbed MoS2 monolayer can be switched from n-to p-type or vice versa. We show that one can realize vanishing n-type/p-type Schottky barrier heights when contacting MoS2 to fluorographane. By applying a perpendicular electric field, the size of the Schottky barrier and the degree of doping can be tuned. Our calculations indicate that a fluorographane monolayer is a promising candidate for bipolar doping of MoS2, which is vital in the design of novel technological applications based on two-dimensional materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000363193800043 Publication Date 2015-09-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited 7 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 (TRGrid 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. ; Approved Most recent IF: 4.123; 2015 IF: 4.493  
  Call Number UA @ lucian @ c:irua:129477 Serial 4182  
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Author Kang, J.; Sahin, H.; Peeters, F.M. pdf  url
doi  openurl
  Title Mechanical properties of monolayer sulphides : a comparative study between MoS2, HfS2 and TiS3 Type A1 Journal article
  Year 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 17 Issue 17 Pages 27742-27749  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The in-plane stiffness (C), Poisson's ratio (nu), Young's modulus and ultimate strength (sigma) along two different crystallographic orientations are calculated for the single layer crystals: MoS2, HfS2 and TiS3 in 1H, 1T and monoclinic phases. We find that MoS2 and HfS2 have isotropic in-plane stiffnesses of 124.24 N m(-1) and 79.86 N m(-1), respectively. While for TiS3 the in-plane stiffness is highly anisotropic due to its monoclinic structure, with C-x = 83.33 N m(-1) and C-y = 133.56 N m(-1) (x and y are parallel to its longer and shorter in-plane lattice vectors.). HfS2 which is in the 1T phase has the smallest anisotropy in its ultimate strength, whereas TiS3 in the monoclinic phase has the largest. Along the armchair direction MoS2 has the largest sigma of 23.48 GPa, whereas along y TiS3 has the largest sigma of 18.32 GPa. We have further analyzed the band gap response of these materials under uniaxial tensile strain, and find that they exhibit different behavior. Along both armchair and zigzag directions, the band gap of MoS2 (HfS2) decreases (increases) as strain increases, and the response is almost isotropic. For TiS3, the band gap decreases when strain is along x, while if strain is along y, the band gap increases first and then decreases beyond a threshold strain value. The different characteristics observed in these sulphides with different structures shed light on the relationship between the structure and properties, which is useful for applications in nanotechnology.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000363193800055 Publication Date 2015-09-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited 83 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 Super-computer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus-Long Marie Curie Fellowship, and J.K. by a FWO Pegasus-Short Marie Curie Fellowship. ; Approved Most recent IF: 4.123; 2015 IF: 4.493  
  Call Number UA @ lucian @ c:irua:129478 Serial 4204  
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Author Berdiyorov, G.R.; Savel'ev, S.; Kusmartsev, F.V.; Peeters, F.M. url  doi
openurl 
  Title Effect of ordered array of magnetic dots on the dynamics of Josephson vortices in stacked SNS Josephson junctions under DC and AC current Type A1 Journal article
  Year 2015 Publication European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B  
  Volume 88 Issue 88 Pages 286  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We use the anisotropic time-dependent Ginzburg-Landau theory to investigate the effect of a square array of out-of-plane magnetic dots on the dynamics of Josephson vortices (fluxons) in artificial stacks of superconducting-normal-superconducting (SNS) Josephson junctions in the presence of external DC and AC currents. Periodic pinning due to the magnetic dots distorts the triangular lattice of fluxons and results in the appearance of commensurability features in the current-voltage characteristics of the system. For the larger values of the magnetization, additional peaks appear in the voltage-time characteristics of the system due to the creation and annihilation of vortex-antivortex pairs. Peculiar changes in the response of the system to the applied current is found resulting in a “superradiant” vortex-flow state at large current values, where a rectangular lattice of moving vortices is formed. Synchronizing the motion of fluxons by adding a small ac component to the biasing dc current is realized. However, we found that synchronization becomes difficult for large magnetization of the dots due to the formation of vortex-antivortex pairs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000363960900002 Publication Date 2015-10-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6028 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.461 Times cited 1 Open Access  
  Notes ; This work was supported by EU Marie Curie (Project No. 253057). ; Approved Most recent IF: 1.461; 2015 IF: 1.345  
  Call Number UA @ lucian @ c:irua:129509 Serial 4166  
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Author Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. url  doi
openurl 
  Title Phonon limited superconducting correlations in metallic nanograins Type A1 Journal article
  Year 2015 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 5 Issue 5 Pages 16515  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Conventional superconductivity is inevitably suppressed in ultra-small metallic grains for characteristic sizes smaller than the Anderson limit. Experiments have shown that above the Anderson limit the critical temperature may be either enhanced or reduced when decreasing the particle size, depending on the superconducting material. In addition, there is experimental evidence that whether an enhancement or a reduction is found depends on the strength of the electronphonon interaction in the bulk. We reveal how the strength of the e-ph interaction interplays with the quantum-size effect and theoretically obtain the critical temperature of the superconducting nanograins in excellent agreement with experimental data. We demonstrate that strong e-ph scattering smears the peak structure in the electronic density-of-states of a metallic grain and enhances the electron mass, and thereby limits the highest T-c achievable by quantum confinement.  
  Address  
  Corporate Author Thesis  
  Publisher Nature Publishing Group Place of Publication London Editor  
  Language Wos 000364647700001 Publication Date 2015-11-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.259 Times cited 9 Open Access  
  Notes ; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Research Foundation Flanders (FWO), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO. M.D.C. acknowledges fruitful discussions with V. Z. Kresin, S. N. Klimin and V. N. Gladilin. ; Approved Most recent IF: 4.259; 2015 IF: 5.578  
  Call Number UA @ lucian @ c:irua:129543 Serial 4224  
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Author de Sousa, A.A.; Chaves, A.; Pereira, T.A.S.; Farias, G.A.; Peeters, F.M. doi  openurl
  Title Quantum tunneling between bent semiconductor nanowires Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 118 Issue 118 Pages 174301  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We theoretically investigate the electronic transport properties of two closely spaced L-shaped semiconductor quantum wires, for different configurations of the output channel widths as well as the distance between the wires. Within the effective-mass approximation, we solve the time-dependent Schrodinger equation using the split-operator technique that allows us to calculate the transmission probability, the total probability current, the conductance, and the wave function scattering between the energy subbands. We determine the maximum distance between the quantum wires below which a relevant non-zero transmission is still found. The transmission probability and the conductance show a strong dependence on the width of the output channel for small distances between the wires. (C) 2015 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000364584200020 Publication Date 2015-11-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 7 Open Access  
  Notes ; A. A. Sousa was financially supported by CAPES, under the PDSE Contract No. BEX 7177/13-5. T. A. S. Pereira was financially supported by PRONEX/CNPq/FAPEMAT 850109/2009 and by CAPES under process BEX 3299/13-9. This work was financially supported by PRONEX/CNPq/FUNCAP, the Science Without Borders program and the bilateral project CNPq-FWO. ; Approved Most recent IF: 2.068; 2015 IF: 2.183  
  Call Number UA @ lucian @ c:irua:129544 Serial 4234  
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Author Martens, K.; Jeong, J.W.; Aetukuri, N.; Rettner, C.; Shukla, N.; Freeman, E.; Esfahani, D.N.; Peeters, F.M.; Topuria, T.; Rice, P.M.; Volodin, A.; Douhard, B.; Vandervorst, W.; Samant, M.G.; Datta, S.; Parkin, S.S.P. url  doi
openurl 
  Title Field Effect and Strongly Localized Carriers in the Metal-Insulator Transition Material VO(2) Type A1 Journal article
  Year 2015 Publication Physical review letters Abbreviated Journal Phys Rev Lett  
  Volume 115 Issue 115 Pages 196401  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The intrinsic field effect, the change in surface conductance with an applied transverse electric field, of prototypal strongly correlated VO(2) has remained elusive. Here we report its measurement enabled by epitaxial VO(2) and atomic layer deposited high-kappa dielectrics. Oxygen migration, joule heating, and the linked field-induced phase transition are precluded. The field effect can be understood in terms of field-induced carriers with densities up to approximately 5x10(13) cm(-2) which are trongly localized, as shown by their low, thermally activated mobility ( approximately 1x10(-3) cm(2)/V s at 300 K). These carriers show behavior consistent with that of Holstein polarons and strongly impact the (opto)electronics of VO(2).  
  Address IBM Research-Almaden, San Jose, California 95120, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000364024800013 Publication Date 2015-11-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9007 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.462 Times cited 28 Open Access  
  Notes ; The authors acknowledge B. Hughes, K. Roche, L. Gao, C. Lada, J. Van Houdt, M. Heyns, J. P. Locquet, J. Delmotte, L. Krupp, L. Clark, and FWO (K. M.). S. D. and N. S. acknowledge LEAST (Low Energy Systems Technology), one of six SRC STARnet Centers, sponsored by MARCO/DARPA, for financial support. ; Approved Most recent IF: 8.462; 2015 IF: 7.512  
  Call Number c:irua:129547 Serial 4051  
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Author Moldovan, D.; Peeters, F.M. pdf  url
doi  openurl
  Title Strain engineering of the electronic properties of bilayer graphene quantum dots: Strain engineering of the electronic properties of bilayer graphene quantum dots Type A1 Journal article
  Year 2015 Publication Physica status solidi: rapid research letters Abbreviated Journal Phys Status Solidi-R  
  Volume 10 Issue 10 Pages 39-45  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study the effect of mechanical deformations on the elec- tronic properties of hexagonal flakes of bilayer graphene. The behavior of electrons induced by triaxial strain can be de- scribed by an effective pseudo-magnetic field which is homo- geneous in the center of the flake. We find that in-plane strain, applied to both layers equally, can break the layer symmetry leading to different behavior in the top and bottom layers of graphene. At low energy, just one of the layers feels

the pseudo-magnetic field: the zero-energy pseudo-Landau level is missing in the second layer, thus creating a gap be- tween the lowest non-zero levels. While the layer asymmetry is most significant at zero energy, interaction with the edges of the flake extends the effect to higher pseudo-Landau lev- els. The behavior of the top and bottom layers may be re- versed by rotating the triaxial strain by 60°.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000368814500005 Publication Date 2015-08-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1862-6254; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.032 Times cited 9 Open Access  
  Notes This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish Government. Approved Most recent IF: 3.032; 2015 IF: 2.142  
  Call Number c:irua:129592 Serial 3970  
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Author Jelić, Ž.L.; Milošević, M.V.; Van de Vondel, J.; Silhanek, A.V. pdf  url
doi  openurl
  Title Stroboscopic phenomena in superconductors with dynamic pinning landscape Type A1 Journal article
  Year 2015 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 5 Issue 5 Pages 14604  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Introducing artificial pinning centers is a well established strategy to trap quantum vortices and increase the maximal magnetic field and applied electric current that a superconductor can sustain without dissipation. In case of spatially periodic pinning, a clear enhancement of the superconducting critical current arises when commensurability between the vortex configurations and the pinning landscape occurs. With recent achievements in (ultrafast) optics and nanoengineered plasmonics it has become possible to exploit the interaction of light with superconductivity, and create not only spatially periodic imprints on the superconducting condensate, but also temporally periodic ones. Here we show that in the latter case, temporal matching phenomena develop, caused by stroboscopic commensurability between the characteristic frequency of the vortex motion under applied current and the frequency of the dynamic pinning. The matching resonances persist in a broad parameter space, including magnetic field, driving current, or material purity, giving rise to unusual features such as externally variable resistance/impedance and Shapiro steps in current-voltage characteristics. All features are tunable by the frequency of the dynamic pinning landscape. These findings open further exploration avenues for using flashing, spatially engineered, and/or mobile excitations on superconductors, permitting us to achieve advanced functionalities.  
  Address Departement de Physique, Universite de Liege, Allee du 6-Aout 17, B-4000 Liege, Belgium  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000362082500001 Publication Date 2015-10-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.259 Times cited 29 Open Access  
  Notes Acknowledgements: This work was supported by the Methusalem Funding of the Flemish Government, the Research Foundation-Flanders (FWO) and the COST Action MP1201. The work of Ž.L.J. and A.V.S. was partially supported by “Mandat d’Impulsion Scientifique” of the F.R.S.-FNRS. Approved Most recent IF: 4.259; 2015 IF: 5.578  
  Call Number c:irua:129807 c:irua:129807 Serial 3980  
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Author Sobrino Fernandez, M.M.; Neek-Amal, M.; Peeters, F.M. url  doi
openurl 
  Title AA-stacked bilayer square ice between graphene layers Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 245428  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Water confined between two graphene layers with a separation of a few A forms a layered two-dimensional ice structure. Using large scale molecular dynamics simulations with the adoptable ReaxFF interatomic potential we found that flat monolayer ice with a rhombic-square structure nucleates between the graphene layers which is nonpolar and nonferroelectric. We provide different energetic considerations and H-bonding results that explain the interlayer and intralayer properties of two-dimensional ice. The controversial AA stacking found experimentally [Algara-Siller et al., Nature (London) 519, 443 (2015)] is consistent with our minimum-energy crystal structure of bilayer ice. Furthermore, we predict that an odd number of layers of ice has the same lattice structure as monolayer ice, while an even number of ice layers exhibits the square ice AA stacking of bilayer ice.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000366731800004 Publication Date 2015-12-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 40 Open Access  
  Notes ; This work was supported by the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number c:irua:130203 Serial 4127  
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Author Dell'Anna, L.; Perali, A.; Covaci, L.; Neilson, D. url  doi
openurl 
  Title Using magnetic stripes to stabilize superfluidity in electron-hole double monolayer graphene Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 220502  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Experiments have confirmed that double monolayer graphene does not generate finite-temperature electron-hole superfluidity, because of very strong screening of the pairing attraction. The linear dispersing energy bands in monolayer graphene block any attempt to reduce the strength of the screening. We propose a hybrid device with two sheets of monolayer graphene in a modulated periodic perpendicular magnetic field. The field preserves the isotropic Dirac cones of the original monolayers but reduces the slope of the cones, making the monolayer Fermi velocity v(F) smaller. We demonstrate that with current experimental techniques, the reduction in vF can weaken the screening sufficiently to allow electron-hole superfluidity at measurable temperatures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000366500100004 Publication Date 2015-12-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 7 Open Access  
  Notes ; We thank M. Zarenia for useful discussions. L.D. acknowledges financial support from MIUR: FIRB 2012, Grant No. RBFR12NLNA_002, and PRIN, Grant No. 2010LLKJBX. A.P. and D.N. acknowledge financial support from University of Camerino FAR project CESEMN. L.C. acknowledges financial support from Flemish Science Foundation (FWO). ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number c:irua:130211 Serial 4069  
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Author Missault, N.; Vasilopoulos, P.; Vargiamidis, V.; Peeters, F.M.; Van Duppen, B. url  doi
openurl 
  Title Spin- and valley-dependent transport through arrays of ferromagnetic silicene junctions Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 195423  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study ballistic transport of Dirac fermions in silicene through arrays of barriers, of width d, in the presence of an exchange field M and a tunable potential of height U or depth-U. The spin-and valley-resolved conductances as functions of U or M, exhibit resonances away from the Dirac point (DP) and close to it a pronounced dip that becomes a gap when a critical electric field E-z is applied. This gap widens by increasing the number of barriers and can be used to realize electric field-controlled switching of the current. The spin p(s) and valley p(v) polarizations of the current near the DP increase with Ez or M and can reach 100% for certain of their values. These field ranges widen significantly by increasing the number of barriers. Also, ps and pv oscillate nearly periodically with the separation between barriers or wells and can be inverted by reversing M.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000364998100006 Publication Date 2015-11-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 54 Open Access  
  Notes ; This work was supported by the Canadian NSERC Grant No. OGP0121756 (P.V.) and by the Flemish Science Foundation (FWO-Vl) with a Ph.D. research grant (B.V.D.). ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number UA @ lucian @ c:irua:130264 Serial 4247  
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Author Kang, J.; Horzum, S.; Peeters, F.M. url  doi
openurl 
  Title Heterostructures of graphene and nitrogenated holey graphene: Moire pattern and Dirac ring Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 195419  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Nitrogenated holey graphene (NHG) is a recently synthesized two-dimensional material. In this paper the structural and electronic properties of heterostructures of graphene and NHG are investigated using first-principles and tight-binding calculations. Due to the lattice mismatch between NHG and graphene, the formation of a moire pattern is preferred in the graphene/NHG heterostructure, instead of a lattice-coherent structure. In moire-patterned graphene/NHG, the band gap opening at the K point is negligible, and the linear band dispersion of graphene survives. Applying an electric field modifies the coupling strength between the two atomic layers. The Fermi velocity upsilon(F) is reduced as compared to the one of pristine graphene, and its magnitude depends on the twist angle theta between graphene and NHG: For theta = 0 degrees, upsilon(F) is 30% of that of graphene, and it increases rapidly to a value of 80% with increasing theta. The heterostructure exhibits electron-hole asymmetry in upsilon(F), which is large for small theta. In NHG encapsulated between two graphene layers, a “Dirac ring” appears around the K point. Its presence is robust with respect to the relative stacking of the two graphene layers. These findings can be useful for future applications of graphene/NHG heterostructures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000364998000006 Publication Date 2015-11-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 33 Open Access  
  Notes Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number UA @ lucian @ c:irua:130266 Serial 4189  
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Author Michel, K.H.; Costamagna; Peeters, F.M. pdf  doi
openurl 
  Title Theory of thermal expansion in 2D crystals Type A1 Journal article
  Year 2015 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B  
  Volume 252 Issue 252 Pages 2433-2437  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The thermal expansion alpha(T) in layered crystals is of fundamental and technological interest. As suggested by I. M. Lifshitz in 1952, in thin solid films (crystalline membranes) a negative contribution to alpha(T) is due to anharmonic couplings between in-plane stretching modes and out-of-plane bending (flexural modes). Genuine in-plane anharmonicities give a positive contribution to alpha(T). The competition between these two effects can lead to a change of sign (crossover) from a negative value of alpha(T) in a temperature (T) range T <= T-alpha to a positive value of alpha(T) for T > T-alpha in layered crystals. Here, we present an analytical lattice dynamical theory of these phenomena for a two-dimensional (2D) hexagonal crystal. We start from a Hamiltonian that comprises anharmonic terms of third and fourth order in the lattice displacements. The in-plane and out-of-plane contributions to the thermal expansion are studied as functions of T for crystals of different sizes. Besides, renormalization of the flexural mode frequencies plays a crucial role in determining the crossover temperature T-alpha. Numerical examples are given for graphene where the anharmonic couplings are determined from experiments. The theory is applicable to other layer crystals wherever the anharmonic couplings are known. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000364690400014 Publication Date 2015-08-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-1972 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.674 Times cited 21 Open Access  
  Notes ; We thank B. Verberck, D. Lamoen, and A. Dobry for useful comments. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. This work is supported by the Euro GRAPHENE project CONGRAN. ; Approved Most recent IF: 1.674; 2015 IF: 1.489  
  Call Number UA @ lucian @ c:irua:130281 Serial 4264  
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Author Tahir, M.; Vasilopoulos, P.; Peeters, F.M. url  doi
openurl 
  Title Quantum magnetotransport properties of a MoS2 monolayer Type A1 Journal article
  Year 2016 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 93 Issue 93 Pages 035406  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study transport properties of a MoS2 monolayer in the presence of a perpendicular magnetic field B. We derive and discuss its band structure and take into account spin and valley Zeeman effects. Compared to a conventional two-dimensional electron gas, these effects lead to new quantum Hall plateaus and new peaks in the longitudinal resistivity as functions of the magnetic field. The field B leads to a significant enhancement of the spin splitting in the conduction band, to a beating of the Shubnikov-de Haas (SdH) oscillations in the low-field regime, and to their splitting in the high-field regime. The Zeeman fields suppress significantly the beating of the SdH oscillations in the low-field regime and strongly enhance their splitting at high fields. The spin and valley polarizations show a similar beating pattern at low fields and are clearly separated at high fields in which they attain a value higher than 90%.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000367663500003 Publication Date 2016-01-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 42 Open Access  
  Notes ; This work was supported by the Canadian NSERC Grant No. OGP0121756 (M.T., P.V.) and by the Flemish Science Foundation (FWO-Vl) (F.M.P.). ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:131093 Serial 4233  
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Author Buh, J.; Kabanov, V.; Baranov, V.; Mrzel, A.; Kovic, A.; Mihailovic, D. url  doi
openurl 
  Title Control of switching between metastable superconducting states in delta-MoN nanowires Type A1 Journal article
  Year 2015 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 6 Issue 6 Pages 10250  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The superconducting state in one-dimensional nanosystems is very delicate. While fluctuations of the phase of the superconducting wave function lead to the spontaneous decay of persistent supercurrents in thin superconducting wires and nanocircuits, discrete phase-slip fluctuations can also lead to more exotic phenomena, such as the appearance of metastable superconducting states in current-bearing wires. Here we show that switching between different metastable superconducting states in d-MoN nanowires can be very effectively manipulated by introducing small amplitude electrical noise. Furthermore, we show that deterministic switching between metastable superconducting states with different numbers of phase-slip centres can be achieved in both directions with small electrical current pulse perturbations of appropriate polarity. The observed current-controlled bi-stability is in remarkable agreement with theoretically predicted trajectories of the system switching between different limit cycle solutions of a model one-dimensional superconductor.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000367576600002 Publication Date 2015-12-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 8 Open Access  
  Notes ; ; Approved Most recent IF: 12.124; 2015 IF: 11.470  
  Call Number UA @ lucian @ c:irua:131108 Serial 4156  
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Author Brito, B.G.A.; Candido, L.; Hai, G.-Q.; Peeters, F.M. url  doi
openurl 
  Title Quantum effects in a free-standing graphene lattice : path-integral against classical Monte Carlo simulations Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 195416  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In order to study quantum effects in a two-dimensional crystal lattice of a free-standing monolayer graphene, we have performed both path-integral Monte Carlo (PIMC) and classical Monte Carlo (MC) simulations for temperatures up to 2000 K. The REBO potential is used for the interatomic interaction. The total energy, interatomic distance, root-mean-square displacement of the atom vibrations, and the free energy of the graphene layer are calculated. The obtained lattice vibrational energy per atom from the classical MC simulation is very close to the energy of a three-dimensional harmonic oscillator 3k(B)T. The PIMC simulation shows that quantum effects due to zero-point vibrations are significant for temperatures T < 1000 K. The quantum contribution to the lattice vibrational energy becomes larger than that of the classical lattice for T < 400 K. The lattice expansion due to the zero-point motion causes an increase of 0.53% in the lattice parameter. A minimum in the lattice parameter appears at T similar or equal to 500 K. Quantum effects on the atomic vibration amplitude of the graphene lattice and its free energy are investigated.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000368095400004 Publication Date 2015-11-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 22 Open Access  
  Notes ; This research was supported by the Brazilian agencies FAPESP, FAPEG, and CNPq, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number UA @ lucian @ c:irua:131144 Serial 4232  
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