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	Author	Grujić, M.; Zarenia, M.; Tadić, M.; Peeters, F.M.
	Title	Interband optical absorption in a circular graphene quantum dot			Type	A1 Journal article
	Year	2012	Publication	Physica scripta	Abbreviated Journal	Phys Scripta
	Volume	T149	Issue		Pages	014056-014056,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We investigate the energy levels and optical properties of a circular graphene quantum dot in the presence of an external magnetic field perpendicular to the dot. Based on the Dirac-Weyl equation and assuming zero outward current at the edge of the dot we present the results for two different types of boundary conditions, i.e. infinite-mass (IMBC) and zigzag boundary conditions. We found that the dot with zigzag edges displays a zero-energy state in the energy spectra while this is not the case for the IMBCs. For both boundary conditions, the confinement becomes dominated by the magnetic field, where the energy levels converge to the Landau levels as the magnetic field increases. The effect of boundary conditions on the electron-and hole-energy states is found to affect the interband absorption spectra, where we found larger absorption in the case of IMBCs. The selection rules for interband optical transitions are determined and discussed for both boundary conditions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Stockholm	Editor
	Language		Wos	000303523500057	Publication Date	2012-04-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-8949;1402-4896;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.28	Times cited	5	Open Access
	Notes	; This work was supported by the EuroGraphene program of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ;			Approved	Most recent IF: 1.28; 2012 IF: 1.032
	Call Number	UA @ lucian @ c:irua:99136			Serial	1688
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	Author	Arsoski, V.; Čukarić, N.; Tadić, M.; Peeters, F.M.
	Title	Exciton states in a nanocup in the presence of a perpendicular magnetic field			Type	A1 Journal article
	Year	2012	Publication	Physica scripta	Abbreviated Journal	Phys Scripta
	Volume	T149	Issue		Pages	014054-014054,5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The exciton states in a strained (In,Ga)As/GaAs nanocup are theoretically determined. We explore how the nanocup bottom thickness (t) affects the magnetic field dependence of the exciton energy. Strain distribution is computed by the continuum mechanical model under the approximation of isotropic elasticity. The exciton wave functions are expanded into products of the electron and hole envelope functions. For small t, the exciton ground state has zero orbital momentum and exhibits small oscillations of the second derivative when the magnetic field increases. When t approaches the value of the cup height, however, the exciton levels exhibit angular momentum transitions, whose behavior is similar to that for type-II quantum dots. Small oscillations of the oscillator strength for exciton recombination are found when the magnetic field increases. An increase in thickness of the nanocup bottom has only a small effect on those oscillations for the optically active exciton states, but the exciton ground state becomes dark when the magnetic field increases. Hence, the results of our calculations show that an increase in thickness of the nanocup bottom transforms the exciton ground energy level dependence on magnetic field from the one characteristic of type-I rings to the one characteristic of type-II dots.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Stockholm	Editor
	Language		Wos	000303523500055	Publication Date	2012-04-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-8949;1402-4896;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.28	Times cited	2	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; 2012 IF: 1.032
	Call Number	UA @ lucian @ c:irua:99135			Serial	1117
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	Author	Chen, Y.; Shanenko, A.A.; Perali, A.; Peeters, F.M.
	Title	Superconducting nanofilms : molecule-like pairing induced by quantum confinement			Type	A1 Journal article
	Year	2012	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	24	Issue	18	Pages	185701-185701,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Quantum confinement of the perpendicular motion of electrons in single-crystalline metallic superconducting nanofilms splits the conduction band into a series of single-electron subbands. A distinctive feature of such a nanoscale multi-band superconductor is that the energetic position of each subband can vary significantly with changing nanofilm thickness, substrate material, protective cover and other details of the fabrication process. It can occur that the bottom of one of the available subbands is situated in the vicinity of the Fermi level. We demonstrate that the character of the superconducting pairing in such a subband changes dramatically and exhibits a clear molecule-like trend, which is very similar to the well-known crossover from the Bardeen-Cooper-Schrieffer regime to Bose-Einstein condensation (BCS-BEC) observed in trapped ultracold fermions. For Pb nanofilms with thicknesses of 4 and 5 monolayers (MLs) this will lead to a spectacular scenario: up to half of all the Cooper pairs nearly collapse, shrinking in the lateral size (parallel to the nanofilm) down to a few nanometers. As a result, the superconducting condensate will be a coherent mixture of almost molecule-like fermionic pairs with ordinary, extended Cooper pairs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000303500900018	Publication Date	2012-04-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0953-8984;1361-648X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.649	Times cited	26	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl). AAS thanks A Bianconi, M D Croitoru and A V Vagov for useful discussions. AAS acknowledges the hospitality and fruitful interactions with G C Strinati, P Pieri and D Neilson during his visit to the University of Camerino, supported by the School of Advanced Studies of the University of Camerino. ;			Approved	Most recent IF: 2.649; 2012 IF: 2.355
	Call Number	UA @ lucian @ c:irua:98223			Serial	3357
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	Author	Lajevardipour, A.; Neek-Amal, M.; Peeters, F.M.
	Title	Thermomechanical properties of graphene : valence force field model approach			Type	A1 Journal article
	Year	2012	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	24	Issue	17	Pages	175303-175303,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using the valence force field model of Perebeinos and Tersoff (2009 Phys. Rev. B 79 241409(R)), different energy modes of suspended graphene subjected to tensile or compressive strain are studied. By carrying out Monte Carlo simulations it is found that: (i) only for small strains (vertical bar epsilon vertical bar (sic) 0.02) is the total energy symmetrical in the strain, while it behaves completely differently beyond this threshold; (ii) the important energy contributions in stretching experiments are stretching, angle bending, an out-of-plane term, and a term that provides repulsion against pi-pi misalignment; (iii) in compressing experiments the two latter terms increase rapidly, and beyond the buckling transition stretching and bending energies are found to be constant; (iv) from stretching-compressing simulations we calculated the Young's modulus at room temperature 350 +/- 3.15 N m(-1), which is in good agreement with experimental results (340 +/- 50 N m(-1)) and with ab initio results (322-353) N m(-1); (v) molar heat capacity is estimated to be 24.64 J mol(-1) K-1 which is comparable with the Dulong-Petit value, i. e. 24.94 J mol(-1) K-1, and is almost independent of the strain; (vi) nonlinear scaling properties are obtained from height-height correlations at finite temperature; (vii) the used valence force field model results in a temperature independent bending modulus for graphene, and (viii) the Gruneisen parameter is estimated to be 0.64.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000303499700012	Publication Date	2012-04-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0953-8984;1361-648X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.649	Times cited	29	Open Access
	Notes	; We acknowledge helpful comments by V Perebeinos, S Costamagna, A Fasolino and J H Los. This work was supported by the Flemish science foundation (FWO-Vl) and the Belgium Science Policy (IAP). ;			Approved	Most recent IF: 2.649; 2012 IF: 2.355
	Call Number	UA @ lucian @ c:irua:99123			Serial	3639
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	Author	Yang, W.; Misko, V.R.; Nelissen, K.; Kong, M.; Peeters, F.M.
	Title	Using self-driven microswimmers for particle separation			Type	A1 Journal article
	Year	2012	Publication	Soft matter	Abbreviated Journal	Soft Matter
	Volume	8	Issue	19	Pages	5175-5179
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Microscopic self-propelled swimmers capable of autonomous navigation through complex environments provide appealing opportunities for localization, pick-up and delivery of micro and nanoscopic objects. Inspired by motile cells and bacteria, man-made microswimmers have been fabricated, and their motion in patterned surroundings has been experimentally studied. We propose to use self-driven artificial microswimmers for the separation of binary mixtures of colloids. We revealed different regimes of separation, including one with a velocity inversion. Our findings could be of use for various biological and medical applications.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000303208700009	Publication Date	2012-03-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1744-683X;1744-6848;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.889	Times cited	45	Open Access
	Notes	; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-V1) (Belgium), the National Natural Science Foundation of China (No. 11047111), the State Key Program of National Natural Science of China (No. 51135007), the Research Fund for the Doctoral Program of Higher Education of China (No. 20111415120002), and the Major State Basic Research Development Program of China (973) (No. 2009CB724201). ;			Approved	Most recent IF: 3.889; 2012 IF: 3.909
	Call Number	UA @ lucian @ c:irua:98326			Serial	3826
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	Author	Barbier, M.; Papp, G.; Peeters, F.M.
	Title	Snake states and Klein tunneling in a graphene Hall bar with a pn-junction			Type	A1 Journal article
	Year	2012	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	100	Issue	16	Pages	163121-163121,3
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The Hall (R-H) and bend (R-B) resistances of a graphene Hall bar structure containing a pn-junction are calculated when in the ballistic regime. The simulations are done using the billiard model. Introducing a pn-junction-dividing the Hall bar geometry in two regions-leads to two distinct regimes exhibiting very different physics: (1) both regions are of n-type and (2) one region is n-type and the other p-type. In regime (1), a “Hall plateau”-an enhancement of the resistance-appears for R-H. On the other hand, in regime (2), we found a negative R-H, which approaches zero for large B. The bend resistance is highly asymmetric in regime (2) and the resistance increases with increasing magnetic field B in one direction while it reduces to zero in the other direction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704667]
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000303128500064	Publication Date	2012-04-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	20	Open Access
	Notes	; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-EuroGRAPHENE project CONGRAN. ;			Approved	Most recent IF: 3.411; 2012 IF: 3.794
	Call Number	UA @ lucian @ c:irua:99129			Serial	3047
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	Author	Ludu, A.; Milošević, M.V.; Peeters, F.M.
	Title	Vortex states in axially symmetric superconductors in applied magnetic field			Type	A1 Journal article
	Year	2012	Publication	Sn – 0378-4754	Abbreviated Journal	Math Comput Simulat
	Volume	82	Issue	7	Pages	1258-1270
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We solve analytically the linearized Ginzburg-Landau (GL) equation in the presence of an uniform magnetic field with cylindrical boundary conditions. The solution of the non-linear GL equation is provided as an expansion in the basis of linearized solutions. We present examples of the resulting vortex structure for a solid and perforated superconducting cylinder. (C) 2012 IMACS. Published by Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000303097000009	Publication Date	2012-02-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0378-4754;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.218	Times cited	1	Open Access
	Notes	; ;			Approved	Most recent IF: 1.218; 2012 IF: 0.836
	Call Number	UA @ lucian @ c:irua:98300			Serial	3887
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	Author	Shakouri, K.; Szafran, B.; Esmaeilzadeh, M.; Peeters, F.M.
	Title	Effective spin-orbit interaction Hamiltonian for quasi-one-dimensional quantum rings			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	16	Pages	165314-165314,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The effective Hamiltonian for an electron in a quasi-one-dimensional quantum ring in the presence of spin-orbit interactions is derived. We demonstrate that, when both coupling types are simultaneously present, the effective Hamiltonian derived by the lowest-radial-state approximation produces energy spectra and charge densities which deviate strongly from the exact ones. For equal Rashba and Dresselhaus coupling constants the lowest-radial-state approximation opens artifactal avoided crossings in the energy spectra and deforms the circular symmetry of the confined charge densities. In this case, there does not exist a ring thin enough to justify the restriction to the lowest radially quantized energy state. We derive the effective Hamiltonian accounting for both the lowest and the first excited radial states, and show that the inclusion of the latter restores the correct features of the exact solution. Relation of this result to the states of a quantum wire is also discussed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000303068800006	Publication Date	2012-04-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	32	Open Access
	Notes	; This work was partially supported by Polish Ministry of Science and Higher Education and its grants for Scientific Research. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:98258			Serial	855
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	Author	Clem, J.R.; Mawatari, Y.; Berdiyorov, G.R.; Peeters, F.M.
	Title	Predicted field-dependent increase of critical currents in asymmetric superconducting nanocircuits			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	14	Pages	144511-144511,16
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The critical current of a thin superconducting strip of width W much larger than the Ginzburg-Landau coherence length xi but much smaller than the Pearl length Lambda = 2 lambda(2)/d is maximized when the strip is straight with defect-free edges. When a perpendicular magnetic field is applied to a long straight strip, the critical current initially decreases linearly with H but then decreases more slowly with H when vortices or antivortices are forced into the strip. However, in a superconducting strip containing sharp 90 degrees or 180 degrees turns, the zero-field critical current at H = 0 is reduced because vortices or antivortices are preferentially nucleated at the inner corners of the turns, where current crowding occurs. Using both analytic London-model calculations and time-dependent Ginzburg-Landau simulations, we predict that in such asymmetric strips the resulting critical current can be increased by applying a perpendicular magnetic field that induces a current-density contribution opposing the applied current density at the inner corners. This effect should apply to all turns that bend in the same direction.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000302611100004	Publication Date	2012-04-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	40	Open Access
	Notes	; This research, supported in part by the US Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering, was performed in part at the Ames Laboratory, which is operated for the US Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358. This work also was supported in part by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). G.R.B. acknowledges individual support from FWO-Vlaanderen. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:98263			Serial	2695
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	Author	Saniz, R.; Partoens, B.; Peeters, F.M.
	Title	Green function approach to superconductivity in nanowires			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	14	Pages	144504-144504,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Superconductivity in nanowires made of weak coupling superconductor materials is investigated using a Green function approach. We show that these are multigap systems in which the ratio Delta(T)/k(B)T(c) is to a large extent similar to what is observed in some high-T-c two-gap systems, such as MgB2 and some of the Fe-based superconductors. On the other hand, because of confinement, the superfluid density has a temperature behavior of the form n(s)(T) = 1 – (T/T-c)(3) near T-c, thus deviating from the BCS behavior for bulk superconductors.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000302290700006	Publication Date	2012-04-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	1	Open Access
	Notes	; This work was supported by FWO-Vl and the Belgian Science Policy (IAP). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97764			Serial	1381
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	Author	Kishore, V.V.R.; Čukarić, N.; Partoens, B.; Tadić, M.; Peeters, F.M.
	Title	Hole subbands in freestanding nanowires : six-band versus eight-band k.p modelling			Type	A1 Journal article
	Year	2012	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	24	Issue	13	Pages	135302-135302,10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The electronic structure of GaAs, InAs and InSb nanowires is studied using the six-band and the eight-band k.p models. The effect of the different Luttinger-like parameters (in the eight-band model) on the hole band structure is investigated. Although GaAs nanostructures are often treated within a six-band model because of the large bandgap, it is shown that an eight-band model is necessary for a correct description of its hole spectrum. The camel-back structure usually found in the six-band model is not always present in the eight-band model. This camel-back structure depends on the interaction between light and heavy holes, especially the ones with opposite spin. The latter effect is less pronounced in an eight-band model, but could be very sensitive to the Kane inter-band energy (E-P) value.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000302120100007	Publication Date	2012-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0953-8984;1361-648X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.649	Times cited	13	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), Belgian Science Policy (IAP) and the Ministry of Education and Science of Serbia. ;			Approved	Most recent IF: 2.649; 2012 IF: 2.355
	Call Number	UA @ lucian @ c:irua:97763			Serial	1479
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	Author	Lucena, D.; Tkachenko, D.V.; Nelissen, K.; Misko, V.R.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M.
	Title	Transition from single-file to two-dimensional diffusion of interacting particles in a quasi-one-dimensional channel			Type	A1 Journal article
	Year	2012	Publication	Physical review : E : statistical, nonlinear, and soft matter physics	Abbreviated Journal	Phys Rev E
	Volume	85	Issue	3:1	Pages	031147-031147,12
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Diffusive properties of a monodisperse system of interacting particles confined to a quasi-one-dimensional channel are studied using molecular dynamics simulations. We calculate numerically the mean-squared displacement (MSD) and investigate the influence of the width of the channel (or the strength of the confinement potential) on diffusion in finite-size channels of different shapes (i.e., straight and circular). The transition from single-file diffusion to the two-dimensional diffusion regime is investigated. This transition [ regarding the calculation of the scaling exponent (alpha) of the MSD <Delta x(2)(t)> proportional to t(alpha)] as a function of the width of the channel is shown to change depending on the channel's confinement profile. In particular, the transition can be either smooth (i.e., for a parabolic confinement potential) or rather sharp (i.e., for a hard-wall potential), as distinct from infinite channels where this transition is abrupt. This result can be explained by qualitatively different distributions of the particle density for the different confinement potentials.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	Woodbury (NY)	Editor
	Language		Wos	000302117900003	Publication Date	2012-03-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1539-3755;1550-2376;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.366	Times cited	38	Open Access
	Notes	; This work was supported by CNPq, FUNCAP (Pronex grant), the “Odysseus” program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), the bilateral program between Flanders and Brazil, and the collaborative program CNPq-FWO-Vl. ;			Approved	Most recent IF: 2.366; 2012 IF: 2.313
	Call Number	UA @ lucian @ c:irua:97784			Serial	3699
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	Author	Neek-Amal, M.; Peeters, F.M.
	Title	Effect of grain boundary on the buckling of graphene nanoribbons			Type	A1 Journal article
	Year	2012	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	100	Issue	10	Pages	101905-101905,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The buckling of graphene nano-ribbons containing a grain boundary is studied using atomistic simulations where free and supported boundary conditions are invoked. We consider the buckling transition of two kinds of grain boundaries with special symmetry. When graphene contains a large angle grain boundary with theta = 21.8 degrees, the buckling strains are larger than those of perfect graphene when the ribbons with free (supported) boundary condition are subjected to compressive tension parallel (perpendicular) to the grain boundary. This is opposite for the results of theta = 32.2 degrees. The shape of the deformations of the buckled graphene nanoribbons depends on the boundary conditions, the presence of the particular used grain boundaries, and the direction of applied in-plane compressive tension. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3692573]
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000301655500021	Publication Date	2012-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-6951;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.411	Times cited	18	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ;			Approved	Most recent IF: 3.411; 2012 IF: 3.794
	Call Number	UA @ lucian @ c:irua:97794			Serial	809
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	Author	Berdiyorov, G.R.; Hernández-Nieves, A.D.; Milošević, M.V.; Peeters, F.M.; Dominguez, D.
	Title	Flux-quantum-discretized dynamics of magnetic flux entry, exit, and annihilation in current-driven mesoscopic type-I superconductors			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	9	Pages	092502-092502,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study nonlinear flux dynamics in a current-carrying type-I superconductor. The stray magnetic field of the current induces the intermediate state, where nucleation of flux domains is discretized to a single fluxoid at a time, while their final shape (tubular or laminar), size, and nucleation rate depend on applied current and edge conditions. The current induces opposite flux domains on opposite sides of the sample, and subsequently drives them to annihilation-which is also discretized, as a sequence of vortex-antivortex pairs. The discretization of both nucleation and annihilation leaves measurable traces in the voltage across the sample and in locally probed magnetization. The reported dynamic phenomena thus provide an unambiguous proof of a flux quantum being the smallest building block of the intermediate state in type-I superconductors.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000301183000002	Publication Date	2012-03-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	14	Open Access
	Notes	; This work was supported by the Belgian Science Policy (IAP), the Flemish Science Foundation (FWO-Vl), and the collaborative project FWO-MINCyT (Project No. FW/08/01). G. R. B. and A. D. H acknowledge support from FWO-Vl. A. D. H. and D. D. acknowledge support from CONICET, CNEA, and ANPCyT (Grant No. PICT07-824). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97180			Serial	1243
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	Author	de Oliveira, E.L.; Albuquerque, E.L.; de Sousa, J.S.; Farias, G.A.; Peeters, F.M.
	Title	Configuration-interaction excitonic absorption in small Si/Ge and Ge/Si core/shell nanocrystals			Type	A1 Journal article
	Year	2012	Publication	The journal of physical chemistry: C : nanomaterials and interfaces	Abbreviated Journal	J Phys Chem C
	Volume	116	Issue	7	Pages	4399-4407
	Keywords	A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
	Abstract	The excitonic properties of Si(core)/Ge(shell) and Ge(core)/Si(shell) nanocrystals (NC's) with diameters of similar to 1.9 nm are investigated using a combination density functional ab initio method to obtain the single particle wave functions and a configuration interaction method to compute the exciton fine structure and absorption coefficient. These core/shell structures exhibit type II confinement, which is more pronounced for the Si/Ge NC as a consequence of strain. The absorption coefficients of these NC's exhibit a single dominant peak, which has a much larger oscillator strength than the multipeaks found for pure Si and Ge NC's. The exciton lifetime in Si, Ge, and Ge/Si shows a small i:emperature dependence in the range 10-300 K, whereas in Si/Ge, the exciton lifetime decreases more than an order of magnitude in the same temperature range.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000301156500007	Publication Date	2012-01-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1932-7447;1932-7455;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.536	Times cited	44	Open Access
	Notes	; The authors acknowledge financial support from CNPq and the bilateral program between Flanders and Brazil and the Belgian Science Foundation (IAP). ;			Approved	Most recent IF: 4.536; 2012 IF: 4.814
	Call Number	UA @ lucian @ c:irua:113045			Serial	482
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	Author	Verberck, B.; Partoens, B.; Peeters, F.M.; Trauzettel, B.
	Title	Strain-induced band gaps in bilayer graphene			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	12	Pages	125403-125403,10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We present a tight-binding investigation of strained bilayer graphene within linear elasticity theory, focusing on the different environments experienced by the A and B carbon atoms of the different sublattices. We find that the inequivalence of the A and B atoms is enhanced by the application of perpendicular strain epsilon(zz), which provides a physical mechanism for opening a band gap, most effectively obtained when pulling the two graphene layers apart. In addition, perpendicular strain introduces electron-hole asymmetry and can result in linear electronic dispersion near the K point. Our findings suggest experimental means for strain-engineered band gaps in bilayer graphene.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000301113200005	Publication Date	2012-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	53	Open Access
	Notes	; The authors would like to acknowledge O. Leenaerts, E. Mariani, K. H. Michel, and J. Schelter for useful discussions. B. V. was financially supported by the Flemish Science Foundation (FWO-Vl). This work was financially supported by the ESF program EuroGraphene under projects CONGRAN and ENTS as well as by the DFG. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97181			Serial	3168
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	Author	Krstajić, P.M.; Peeters, F.M.
	Title	Remote electron plasmon polaron in graphene			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	8	Pages	085436-085436,5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The Coulomb interaction and the correlation of a remote electron with a single layer of graphene is investigated in the presence of a magnetic field applied perpendicular to the graphene layer. The remote electron polarizes the electron gas in the graphene layer, which we describe in terms of excitations of virtual plasmons in graphene. The composite quasiparticle formed by electron plus polarization is called a plasmon polaron. The ground-state energy of this quasiparticle is calculated within perturbation theory for remote electrons in different environments.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000300831900012	Publication Date	2012-02-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	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). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97202			Serial	2869
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	Author	Carvalho, J.C.N.; Nelissen, K.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M.
	Title	Diffusion in a quasi-one-dimensional system on a periodic substrate			Type	A1 Journal article
	Year	2012	Publication	Physical review : E : statistical, nonlinear, and soft matter physics	Abbreviated Journal	Phys Rev E
	Volume	85	Issue	2:1	Pages	021136-021136,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The diffusion of charged particles interacting through a repulsive Yukawa potential, exp(-r/lambda)/r, confined by a parabolic potential in the y direction and subjected to a periodic substrate potential in the x direction is investigated. Langevin dynamic simulations are used to investigate the effect of the particle density, the amplitude of the periodic substrate, and the range of the interparticle interaction potential on the diffusive behavior of the particles. We found that in general the diffusion is suppressed with increasing the amplitude of the periodic potential, but for specific values of the strength of the substrate potential a remarkable increase of the diffusion is found with increasing the periodic potential amplitude. In addition, we found a strong dependence of the diffusion on the specific arrangement of the particles, e. g., single-chain versus multichain configuration. For certain particle configurations, a reentrant behavior of the diffusion is found as a function of the substrate strength due to structural transitions in the ordering of the particles.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	Woodbury (NY)	Editor
	Language		Wos	000300671500007	Publication Date	2012-02-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1539-3755;1550-2376;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.366	Times cited	9	Open Access
	Notes	; This work was supported by the Brazilian agencies CNPq and FUNCAP (PRONEX-Grant), the Flemish Science Foundation (FWO-Vl), and the bilateral projects between Flanders and Brazil and the Flemish Science Foundation (FWO-VI) and CNPq. ;			Approved	Most recent IF: 2.366; 2012 IF: 2.313
	Call Number	UA @ lucian @ c:irua:97203			Serial	698
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	Author	Nasr Esfahani, D.; Covaci, L.; Peeters, F.M.
	Title	Electric-field-induced shift of the Mott metal-insulator transition in thin films			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	8	Pages	085110-085110,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The ground-state properties of a paramagnetic Mott insulator at half-filling are investigated in the presence of an external electric field using the inhomogeneous Gutzwiller approximation for a single-band Hubbard model in a slab geometry. We find that the metal-insulator transition is shifted toward higher Hubbard repulsions by applying an electric field perpendicular to the slab. The main reason is the accumulation of charges near the surface. The spatial distribution of site-dependent quasiparticle weight shows that it is maximal in a few layers beneath the surface, while the central sites where the field is screened have a very low quasiparticle weight. Our results show that above a critical-field value, states near the surface will be metallic, while the bulk quasiparticle weight is extremely suppressed but never vanishing, even for large Hubbard repulsions above the bulk zero-field critical value. Below the critical-field value, our results hint toward an insulating state in which the electric field is totally screened and the slab is again at half-filling.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000300240100002	Publication Date	2012-02-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	3	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97208			Serial	884
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	Author	Latimer, M.L.; Berdiyorov, G.R.; Xiao, Z.L.; Kwok, W.K.; Peeters, F.M.
	Title	Vortex interaction enhanced saturation number and caging effect in a superconducting film with a honeycomb array of nanoscale holes			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	1	Pages	012505-012505,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The electrical transport properties of a MoGe thin film with a honeycomb array of nanoscale holes are investigated. The critical current of the system shows nonmatching anomalies as a function of applied magnetic field, enabling us to distinguish between multiquanta vortices trapped in the holes and interstitial vortices located between the holes. The number of vortices trapped in each hole is found to be larger than the saturation number predicted for an isolated hole and shows a nonlinear field dependence, leading to the caging effect as predicted from the Ginzburg-Landau (GL) theory. Our experimental results are supplemented by numerical simulations based on the GL theory.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000299867200001	Publication Date	2012-01-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	41	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP) (theory) and by the US Department of Energy (DOE) Grant No. DE-FG02-06ER46334 (experiment). G. R. B. acknowledges an individual grant from FWO-Vl. W. K. K. acknowledges support from DOE BES under Contract No. DE-AC02-06CH11357, which also funds Argonne's Center for Nanoscale Materials (CNM), where the focused-ion-beam milling was performed. M.L.L was a recipient of the NIU/ANL Distinguished Graduate Fellowship. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:96224			Serial	3866
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	Author	Vagov, A.V.; Shanenko, A.A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M.
	Title	Extended Ginzburg-Landau formalism : systematic expansion in small deviation from the critical temperature			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	1	Pages	014502-014502,17
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Based on the Gor'kov formalism for a clean s-wave superconductor, we develop an extended version of the single-band Ginzburg-Landau (GL) theory by means of a systematic expansion in the deviation from the critical temperature T(c), i.e., tau = 1 – T/T(c). We calculate different contributions to the order parameter and the magnetic field: the leading contributions (proportional to tau(1/2) in the order parameter and. t in the magnetic field) are controlled by the standard GL theory, while the next-to-leading terms (proportional to tau(3/2) in the gap and proportional to tau(2) in the magnetic field) constitute the extended GL (EGL) approach. We derive the free-energy functional for the extended formalism and the corresponding expression for the current density. To illustrate the usefulness of our formalism, we calculate, in a semianalytical form, the temperature-dependent correction to the GL parameter at which the surface energy becomes zero, and analytically, the temperature dependence of the thermodynamic critical field. We demonstrate that the EGL formalism is not just a mathematical extension to the theory: variations of both the gap and the thermodynamic critical field with temperature calculated within the EGL theory are found in very good agreement with the full BCS results down to low temperatures, which dramatically improves the applicability of the formalism compared to its standard predecessor.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000298985100002	Publication Date	2012-01-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	36	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). A. V. V. is grateful to V. Zalipaev for important comments. A. A. S. thanks W. Pogosov for helpful notes. Discussions with E. H. Brandt and A. Perali are appreciated. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:96232			Serial	1155
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	Author	Vodolazov, D.Y.; Peeters, F.M.
	Title	Enhancement of the retrapping current of superconducting microbridges of finite length			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	2	Pages	024508-024508,6
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We theoretically find that the resistance of a superconducting microbridge or nanowire decreases while the retrapping current I(r) for the transition to the superconducting state increases when one suppresses the magnitude of the order parameter vertical bar Delta vertical bar in the attached superconducting leads. This effect is a consequence of the increased energy interval for diffusion of the “hot” nonequilibrium quasiparticles (induced by the oscillations of vertical bar Delta vertical bar in the center of the microbridge) to the leads. The effect is absent in short microbridges (with length less than the coherence length) and it is relatively weak in long microbridges (with length larger than the inelastic relaxation length of the nonequilibrium distribution function). A nonmonotonous dependence of I(r) on the length of the microbridge is predicted. Our results are important for the explanation of the enhancement of the critical current and the appearance of negative magnetoresistance observed in many recent experiments on superconducting microbridges or nanowires.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000298863400005	Publication Date	2012-01-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	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 Russian Foundation for Basic Research, Russian Agency of Education, under the Federal Target Programme “Scientific and Educational Personnel of Innovative Russia in 2009-2013” and the Flemish Science Foundation (FWO-Vl). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:96235			Serial	1065
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	Author	Ao, Z.M.; Hernández-Nieves, A.D.; Peeters, F.M.; Li, S.
	Title	The electric field as a novel switch for uptake/release of hydrogen for storage in nitrogen doped graphene			Type	A1 Journal article
	Year	2012	Publication	Physical chemistry, chemical physics	Abbreviated Journal	Phys Chem Chem Phys
	Volume	14	Issue	4	Pages	1463-1467
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Nitrogen-doped graphene was recently synthesized and was reported to be a catalyst for hydrogen dissociative adsorption under a perpendicular applied electric field (F). In this work, the diffusion of H atoms on N-doped graphene, in the presence and absence of an applied perpendicular electric field, is studied using density functional theory. We demonstrate that the applied field can significantly facilitate the binding of hydrogen molecules on N-doped graphene through dissociative adsorption and diffusion on the surface. By removing the applied field the absorbed H atoms can be released efficiently. Our theoretical calculation indicates that N-doped graphene is a promising hydrogen storage material with reversible hydrogen adsorption/desorption where the applied electric field can act as a switch for the uptake/release processes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000298754500018	Publication Date	2011-11-21
	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	67	Open Access
	Notes	; Financial support of the Vice-Chancellor's Postdoctoral Research Fellowship Program (SIR50/PS19184) and the ECR grant (SIR30/PS24201) from the University of New South Wales are acknowledged. This work is also supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ;			Approved	Most recent IF: 4.123; 2012 IF: 3.829
	Call Number	UA @ lucian @ c:irua:96266			Serial	3578
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	Author	Nowak, M.P.; Szafran, B.; Peeters, F.M.
	Title	Fano resonances and electron spin transport through a two-dimensional spin-orbit-coupled quantum ring			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	84	Issue	23	Pages	235319-235319,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Electron transport through a spin-orbit-coupled quantum ring is investigated within linear response theory. We show that the finite width of the ring results in the appearance of Fano resonances in the conductance. This turns out to be a consequence of the spin-orbit interaction that leads to a breaking of the parity of the states localized in the ring. The resonances appear when the system is close to maxima of Aharonov-Casher conductance oscillations where spin transfer is heavily modified. When the spin-orbit coupling strength is detuned from the Aharonov-Casher maxima the resonances are broadened resulting in a dependence of the spin transport on the electron Fermi energy in contrast to predictions from one-dimensional models.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000298605700002	Publication Date	2011-12-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	19	Open Access
	Notes	; This work was supported by the “Krakow Interdisciplinary PhD Project in Nanoscience and Advanced Nanostructures” operated within the Foundation for Polish Science MPD Programme cofinanced by the EU European Regional Development Fund, Project No. N N202103938 supported by the Ministry of Science and Higher Education (MNiSW) for 2010-2013, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-V1). This research was supported in part by PL-Grid Infrastructure. ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:94292			Serial	1171
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	Author	Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M.; Axt, V.M.
	Title	Parity-fluctuation induced enlargement of the ratio \Delta_E/k_BT_c in metallic grains			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	84	Issue	21	Pages	214518-214518,12
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We investigate how the interplay of quantum confinement and particle number-parity fluctuations affects superconducting correlations in ultra-small metallic grains. Using the number-parity projected BCS formalism we calculate the critical temperature and the excitation gap as a function of the grain size for grains with even and odd number of confined carriers. We show that the experimentally observed anomalous increase of the coupling ratio ΔE/kBTc with decreasing superconducting grain size can be attributed to an enhancement of the number-parity fluctuations in ultra-small grains.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000298114100003	Publication Date	2011-12-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	14	Open Access
	Notes	; This work was supported by the European Community under a Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flamish Science Foundation (FWO-Vl), and the Belgian Science Policy (IAP). M. D. C. thanks A. S. Mel'nikov and N. B. Kopnin for fruitful discussions. ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:94373			Serial	2555
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	Author	Masir, M.R.; Matulis, A.; Peeters, F.M.
	Title	Scattering of Dirac electrons by circular mass barriers : valley filter and resonant scattering			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	84	Issue	24	Pages	245413-245413,9
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The scattering of two-dimensional (2D) massless Dirac electrons is investigated in the presence of a random array of circular mass barriers. The inverse momentum relaxation time and the Hall factor are calculated and used to obtain parallel and perpendicular resistivity components within linear transport theory. We found a nonzero perpendicular resistivity component which has opposite sign for electrons in the different K and K′ valleys. This property can be used for valley filter purposes. The total cross section for scattering on penetrable barriers exhibits resonances due to the presence of quasibound states in the barriers that show up as sharp gaps in the cross section while for Schrödinger electrons they appear as peaks.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000297934500008	Publication Date	2011-12-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	32	Open Access
	Notes	; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro-GRAPHENE within the project CONGRAN. ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:94383			Serial	2951
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	Author	Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M.
	Title	Energy levels of triangular and hexagonal graphene quantum dots : a comparative study between the tight-binding and Dirac equation approach			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	84	Issue	24	Pages	245403-245403,12
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The Dirac equation is solved for triangular and hexagonal graphene quantum dots for different boundary conditions in the presence of a perpendicular magnetic field. We analyze the influence of the dot size and its geometry on their energy spectrum. A comparison between the results obtained for graphene dots with zigzag and armchair edges, as well as for infinite-mass boundary condition, is presented and our results show that the type of graphene dot edge and the choice of the appropriate boundary conditions have a very important influence on the energy spectrum. The single-particle energy levels are calculated as a function of an external perpendicular magnetic field that lifts degeneracies. Comparing the energy spectra obtained from the tight-binding approximation to those obtained from the continuum Dirac equation approach, we verify that the behavior of the energies as a function of the dot size or the applied magnetic field are qualitatively similar, but in some cases quantitative differences can exist.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000297767800008	Publication Date	2011-12-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	145	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE (project CONGRAN), the Bilateral program between Flanders and Brazil, CAPES and the Brazilian Council for Research (CNPq). ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:93961			Serial	1040
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	Author	Covaci, L.; Peeters, F.M.
	Title	Superconducting proximity effect in graphene under inhomogeneous strain			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	84	Issue	24	Pages	241401-241401,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The interplay between quantum Hall states and Cooper pairs is usually hindered by the suppression of the superconducting state due to the strong magnetic fields needed to observe the quantum Hall effect. From this point of view, graphene is special since it allows the creation of strong pseudomagnetic fields due to strain. We show that in a Josephson junction made of strained graphene, Cooper pairs will diffuse into the strained region. The pair correlation function will be sublattice polarized due to the polarization of the local density of states in the zero pseudo-Landau level. We uncover two regimes: (1) one in which the cyclotron radius is larger than the junction length, in which case the supercurrent will be enhanced, and (2) the long junction regime where the supercurrent is strongly suppressed because the junction becomes an insulator. In the latter case quantized Hall states form and Andreev scattering at the normal/superconducting interface will induce edge states. Our numerical calculation has become possible due to an extension of the Chebyshev-Bogoliubovde Gennes method to computations on video cards (GPUs).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000297766600003	Publication Date	2011-12-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	27	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Euro GRAPHENE project CONGRAN. Discussions with Andrey Chaves are gratefully acknowledged. ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:93962			Serial	3364
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	Author	Sena, S.H.R.; Pereira, J.M.; Peeters, F.M.; Farias, G.A.
	Title	Landau levels in asymmetric graphene trilayer			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	84	Issue	20	Pages	205448-205448,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The electronic spectrum of three coupled graphene layers (graphene trilayers) is investigated in the presence of an external magnetic field. We obtain analytical expressions for the Landau level spectrum for both the ABA and ABC type of stacking, which exhibit very different dependence on the magnetic field. We show that layer asymmetry and an external gate voltage can strongly influence the properties of the system.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000297295400018	Publication Date	2011-11-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	30	Open Access
	Notes	; This work was supported by the Brazilian Council for Research (CNPq), the National Council for the Improvement of Higher Education (CAPES), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the bilateral projects between Flanders and Brazil and the CNPq and FWO-Vl. ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:94026			Serial	1773
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	Author	Grujić, M.; Zarenia, M.; Chaves, A.; Tadić, M.; Farias, G.A.; Peeters, F.M.
	Title	Electronic and optical properties of a circular graphene quantum dot in a magnetic field : influence of the boundary conditions			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	84	Issue	20	Pages	205441-205441,12
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	An analytical approach, using the Dirac-Weyl equation, is implemented to obtain the energy spectrum and optical absorption of a circular graphene quantum dot in the presence of an external magnetic field. Results are obtained for the infinite-massand zigzag boundary conditions. We found that the energy spectrum of a dot with the zigzag boundary condition exhibits a zero-energy band regardless of the value of the magnetic field, while for the infinite-mass boundary condition, the zero-energy states appear only for high magnetic fields. The analytical results are compared to those obtained from the tight-binding model: (i) we show the validity range of the continuum model and (ii) we find that the continuum model with the infinite-mass boundary condition describes rather well its tight-binding analog, which can be partially attributed to the blurring of the mixed edges by the staggered potential.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000297295400011	Publication Date	2011-11-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	78	Open Access
	Notes	; This work was supported by the EuroGraphene programme of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP), the bilateral projects between Flanders and Brazil, the Flemish Science Foundation (FWO-Vl), and the Brazilian Research Council (CNPq). ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:94025			Serial	997
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