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	Author	Barbier, M.; Vasilopoulos, P.; Peeters, F.M.
	Title	Kronig-Penney model on bilayer graphene : spectrum and transmission periodic in the strength of the barriers			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	23	Pages	235408-235408,10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We show that the transmission through single and double δ-function potential barriers of strength P=VWb/ℏvF in bilayer graphene is periodic in P with period π. For a certain range of P values we find states that are bound to the potential barrier and that run along the potential barrier. Similar periodic behavior is found for the conductance. The spectrum of a periodic succession of δ-function barriers (Kronig-Penney model) in bilayer graphene is periodic in P with period 2π. For P smaller than a critical value Pc, the spectrum exhibits two Dirac points while for P larger than Pc an energy gap opens. These results are extended to the case of a superlattice of δ-function barriers with P alternating in sign between successive barriers; the corresponding spectrum is periodic in P with period π.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000286766900008	Publication Date	2010-12-06
	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	34	Open Access
	Notes	; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the Canadian NSERC under Grant No. OGP0121756. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:88910			Serial	1768
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	Author	Shakouri, K.; Vasilopoulos, P.; Vargiamidis, V.; Peeters, F.M.
	Title	Integer and half-integer quantum Hall effect in silicene: Influence of an external electric field and impurities			Type	A1 Journal article
	Year	2014	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	90	Issue	23	Pages	235423
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The influence of silicene's strong spin-orbit interaction and of an external electric field E-z on the transport coefficients are investigated in the presence of a perpendicular magnetic field B. For finite E-z the spin and valley degeneracy of the Landau levels is lifted and leads to additional plateaus in the Hall conductivity, at half-integer values of 4e(2)/h, due to spin intra-Landau-level transitions that are absent in graphene. These plateaus are more sensitive to disorder and thermal broadening than the main plateaus, occurring at integral values of 4e(2)/h, when the Fermi level passes through the Landau levels. We also evaluate the Hall and longitudinal resistivities and critically contrast the results with those for graphene on a substrate.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000346377400004	Publication Date	2014-12-15
	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	; Our work was supported by the Flemish Science Foundation (FWO-VI), the Methusalem Foundation of the Flemish Government, and the Canadian NSERC Grant No. OGP0121756. ;			Approved	Most recent IF: 3.836; 2014 IF: 3.736
	Call Number	UA @ lucian @ c:irua:122771			Serial	1678
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	Author	Masir, M.R.; Vasilopoulos, P.; Matulis, A.; Peeters, F.M.
	Title	Direction-dependent tunneling through nanostructured magnetic barriers in graphene			Type	A1 Journal article
	Year	2008	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	77	Issue	23	Pages	235443,1-11
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000257289500133	Publication Date	2008-06-27
	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	212	Open Access
	Notes				Approved	Most recent IF: 3.836; 2008 IF: 3.322
	Call Number	UA @ lucian @ c:irua:69639			Serial	727
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	Author	Masir, M.R.; Vasilopoulos, P.; Peeters, F.M.
	Title	Wavevector filtering through single-layer and bilayer graphene with magnetic barrier structures			Type	A1 Journal article
	Year	2008	Publication	Applied physics letters	Abbreviated Journal	Appl Phys Lett
	Volume	93	Issue	24	Pages	242103,1-242103,3
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We show that the angular range of the transmission through magnetic barrier structures can be efficiently controlled in single-layer and bilayer graphenes and this renders the structures efficient wavevector filters. As the number of magnetic barriers increases, this range shrinks, the gaps in the transmission versus energy become wider, and the conductance oscillates with the Fermi energy.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000261896400032	Publication Date	2008-12-15
	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	91	Open Access
	Notes				Approved	Most recent IF: 3.411; 2008 IF: 3.726
	Call Number	UA @ lucian @ c:irua:75931			Serial	3910
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	Author	Van Pottelberge, R.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M.
	Title	Graphene quantum dot with a Coulomb impurity : subcritical and supercritical regime			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	24	Pages	245410
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study the influence of confinement on the atomic collapse due to a Coulomb impurity placed at the center of a graphene quantum dot of radius R. We apply the zigzag or infinite-mass boundary condition and consider both a point-size and a finite-size impurity. As a function of the impurity strength Za, the energy spectra are discrete. In the case of the zigzag boundary condition, the degenerate (with respect to the angular momentum m) zero-energy levels are pulled down in energy as Z alpha increases, and they remain below epsilon = – Z alpha. Our results show that the energy levels exhibit a 1/R dependence in the subcritical regime [Z alpha < \|km + 1/2\|, k = 1 (-1) for the K (K') valley]. In the supercritical regime (Z alpha > \|km + 1/2\|) we find a qualitatively very different behavior where the levels decrease as a function of R in a nonmonotonic manner. While the valley symmetry is preserved in the presence of the impurity, we find that the impurity breaks electron-hole symmetry. We further study the energy spectrum of zigzag quantum dots in gapped graphene. Our results show that as the gap increases, the lowest electron states are pushed into the gap by the impurity.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000403072400005	Publication Date	2017-06-13
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	13	Open Access
	Notes	; We thank Massoud Ramezani-Masir and Dean Moldovan for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem funding of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756 (P. V.). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:144197			Serial	4661
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	Author	Zarenia, M.; Vasilopoulos, P.; Peeters, F.M.
	Title	Magnetotransport in periodically modulated 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	24	Pages	245426-245426,10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Magnetotransport in bilayer graphene in the presence of a weak and periodic potential is investigated in the presence of a perpendicular magnetic field B. The modulation broadens the Landau levels into bands and for weak magnetic fields leads to the well-known Weiss oscillations in their bandwidth and their transport coefficients at very low B and to the Shubnikov-de Haas oscillations at larger B. The amplitude of the Weiss oscillations is severely reduced if the periodic potentials applied to the two layers oscillate out of phase. We also contrast some results with those corresponding to single-layer graphene. Relative to them the flat-band condition and the oscillation amplitude differ substantially, due to the interlayer coupling, and agree only when this coupling is extremely weak. We further show that the Hall conductivity exhibits the well-known steps at half-integer and integer multiples of 4e(2)/h in single-layer and bilayer graphene, respectively, even for very weak magnetic fields. The results are pertinent to weak and periodic corrugations when the potential modulation dominates the strain-induced magnetic modulation.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000305253600012	Publication Date	2012-06-14
	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	21	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CON-GRAN), and the Canadian NSERC Grant No. OGP0121756. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:99077			Serial	1934
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	Author	Masir, M.R.; Vasilopoulos, P.; Peeters, F.M.
	Title	Graphene in inhomogeneous magnetic fields : bound, quasi-bound and scattering states			Type	A1 Journal article
	Year	2011	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	23	Issue	31	Pages	315301,1-315301,14
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The electron states in graphene-based magnetic dot and magnetic ring structures and combinations of both are investigated. The corresponding spectra are studied as a function of the radii, the strengths of the inhomogeneous magnetic field and of a uniform background field, the strength of an electrostatic barrier and the angular momentum quantum number. In the absence of an external magnetic field we have only long-lived quasi-bound and scattering states and we assess their influence on the density of states. In addition, we consider elastic electron scattering by a magnetic dot, whose average B vanishes, and show that the Hall and longitudinal resistivities, as a function of the Fermi energy, exhibit a pronounced oscillatory structure due to the presence of quasi-bound states. Depending on the dot parameters this oscillatory structure differs substantially for energies below and above the first Landau level.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000293008900002	Publication Date	2011-07-16
	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	38	Open Access
	Notes	; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE, the Canadian NSERC grant no. OGP0121756 and the Belgian Science Policy (IAP). We acknowledge discussions and correspondence with Professor A Matulis. ;			Approved	Most recent IF: 2.649; 2011 IF: 2.546
	Call Number	UA @ lucian @ c:irua:91176			Serial	1372
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	Author	Masir, M.R.; Vasilopoulos, P.; Peeters, F.M.
	Title	Kronig-Penney model of scalar and vector potentials in graphene			Type	A1 Journal article
	Year	2010	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	22	Issue	46	Pages	465302,1-465302,10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We consider a one-dimensional (1D) superlattice (SL) on graphene consisting of very high and very thin (δ-function) magnetic and potential barriers with zero average potential and zero magnetic field. We calculate the energy spectrum analytically, study it in different limiting cases, and determine the condition under which an electron beam incident on an SL is highly collimated along its direction. In the absence of the magnetic SL the collimation is very sensitive to the value of W/Ws and is optimal for W/Ws = 1, where W is the distance between the positive and negative barriers and L = W + Ws is the size of the unit cell. In the presence of only the magnetic SL the collimation decreases and the symmetry of the spectrum around ky is broken for W/W_s\neq 1 . In addition, a gap opens which depends on the strength of the magnetic field. We also investigate the effect of spatially separated potential and magnetic δ-function barriers and predict a better collimation in specific cases.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000283838800004	Publication Date	2010-11-05
	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	41	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), and the Canadian NSERC Grant No. OGP0121756. ;			Approved	Most recent IF: 2.649; 2010 IF: 2.332
	Call Number	UA @ lucian @ c:irua:85807			Serial	1767
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