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	Author	Ao, Z.M.; Peeters, F.M.
	Title	High-capacity hydrogen storage in Al-adsorbed graphene			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	20	Pages	205406,1-205406,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	A high-capacity hydrogen storage mediumAl-adsorbed grapheneis proposed based on density-functional theory calculations. We find that a graphene layer with Al adsorbed on both sides can store hydrogen up to 13.79 wt % with average adsorption energy −0.193 eV/H2. Its hydrogen storage capacity is in excess of 6 wt %, surpassing U. S. Department of Energy (DOEs) target. Based on the binding-energy criterion and molecular-dynamics calculations, we find that hydrogen storage can be recycled at near ambient conditions. This high-capacity hydrogen storage is due to the adsorbed Al atoms that act as bridges to link the electron clouds of the H2 molecules and the graphene layer. As a consequence, a two-layer arrangement of H2 molecules is formed on each side of the Al-adsorbed graphene layer. The H2 concentration in the hydrogen storage medium can be measured by the change in the conductivity of the graphene layer.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000278144500082	Publication Date	2010-05-06
	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	219	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO) and the Belgian Science Policy (IAP). ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:83386			Serial	1422
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	Author	Chen, Y.; Shanenko, A.A.; Peeters, F.M.
	Title	Hollow nanocylinder: multisubband superconductivity induced by quantum confinement			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	13	Pages	134523-134523:11
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Quantization of the transverse electron motion in high-quality superconducting metallic nanowires and nanofilms results in the formation of well-distinguished single-electron subbands. They shift in energy with changing thickness, which is known to cause quantum-size superconducting oscillations. The formation of multiple subbands results in a multigap structure induced by the interplay between quantum confinement and Andreev mechanism. We investigate multisubband superconductivity in a hollow nanocylinder by numerically solving the Bogoliubov-de Gennes equations. When changing the inner radius and thickness of the hollow nanocylinder, we find a crossover from an irregular pattern of quantum-size superconducting oscillations, typical of nanowires, to an almost regular regime, specific for superconducting nanofilms. At this crossover the multigap structure becomes degenerate. The ratio of the critical temperature to the energy gap increases and approaches its bulk value while being reduced by 20-30% due to Andreev-type states driven by quantum confinement in the irregular regime.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000277207900098	Publication Date	2010-04-26
	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	21	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-VI), the Interuniversity Attraction Poles Programme, Belgian States, Belgian Science Policy (IAP) and the ESF-AQDJJ network. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:95623			Serial	1481
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	Author	Nistor, S.V.; Stefan, M.; Nistor, L.C.; Goovaerts, E.; Van Tendeloo, G.
	Title	Incorporation and localization of substitutional Mn²⁺ ions in cubic ZnS quantum dots			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	3	Pages	035336,1-035336,6
	Keywords	A1 Journal article; Nanostructured and organic optical and electronic materials (NANOrOPT); Electron microscopy for materials research (EMAT)
	Abstract	Multifrequency electron paramagnetic resonance (EPR) and high resolution transmission electron microscopy (HRTEM) investigations were performed on small (2 nm) cubic ZnS nanocrystals (quantum dotsQDs) doped with 0.2% mol Mn2+, self-assembled into a mesoporous structure. The EPR data analysis shows that the substitutional Mn2+ ions are localized at Zn2+ sites subjected to a local axial lattice distortion, resulting in the observed zero-field-splitting parameter \|D\|=41×10−4 cm−1. The local distortion is attributed to the presence in the second shell of ligands of a stacking fault or twin, which alters the normal stacking sequence of the cubic structure. The HRTEM results confirm the presence of such extended planar defects in a large percentage of the investigated QDs, which makes possible the proposed substitutional Mn2+ impurity ions localization model. Based on these results it is suggested that the high doping levels of Mn2+ ions observed in cubic ZnS and possible in other II-VI semiconductor QDs prepared at low temperatures can be explained by the assistance of the extended lattice defects in the impurities incorporation.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000277970900007	Publication Date	2010-01-29
	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	55	Open Access
	Notes	Fwo			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:83649			Serial	1597
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	Author	Gehrke, K.; Moshnyaga, V.; Samwer, K.; Lebedev, O.I.; Verbeeck, J.; Kirilenko, D.; Van Tendeloo, G.
	Title	Interface controlled electronic variations in correlated heterostructures			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	11	Pages	113101,1-113101,4
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	An interface modification of (LaCa)MnO3-BaTiO3 superlattices was found to massively influence magnetic and magnetotransport properties. Moreover it determines the crystal structure of the manganite layers, changing it from orthorhombic (Pnma) for the conventional superlattice (cSL), to rhombohedral (R3̅ c) for the modified one (mSL). While the cSL shows extremely nonlinear ac transport, the mSL is an electrically homogeneous material. The observations go beyond an oversimplified picture of dead interface layers and evidence the importance of electronic correlations at perovskite interfaces.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000281643200001	Publication Date	2010-09-07
	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	9	Open Access
	Notes	This work was supported by DFG via SFB 602, TPA2.			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:84249UA @ admin @ c:irua:84249			Serial	1691
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	Author	Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H.
	Title	Interplay of atomic displacement in the quantum magnet (CuCI)LaNb₂O₇			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	5	Pages	054107,1-054107,12
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000280849400001	Publication Date	2010-08-12
	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	13	Open Access
	Notes				Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:83991			Serial	1706
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	Author	Li, L.L.; Xu, W.; Peeters, F.M.
	Title	Intrinsic optical anisotropy of [001]-grown short-period InAs/GaSb superlattices			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	235422-235422,10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We theoretically investigate the intrinsic optical anisotropy or polarization induced by the microscopic interface asymmetry (MIA) in no-common-atom (NCA) InAs/GaSb superlattices (SLs) grown along the [001] direction. The eight-band K⋅P model is used to calculate the electronic band structures and incorporates the MIA effect. A Boltzmann equation approach is employed to calculate the optical properties. We found that in NCA InAs/GaSb SLs, the MIA effect causes a large in-plane optical anisotropy for linearly polarized light and the largest anisotropy occurs for light polarized along the [110] and [11̅ 0] directions. The relative difference between the optical-absorption coefficient for [110]-polarized light and that for [11̅ 0]-polarized light is found to be larger than 50%. The dependence of the in-plane optical anisotropy on temperature, photoexcited carrier density, and layer width is examined in detail. This study is important for optical devices which require the polarization control and selectivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000286768800007	Publication Date	2010-12-13
	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	18	Open Access
	Notes	; This work was supported partly by the Flemish Science Foundation (FWO-VL), the Belgium Science Policy (IAP), the NSF of China (Grants No. 10664006, No. 10504036, and No. 90503005), Special Funds of 973 Project of China (Grant No. 2005CB623603), and Knowledge Innovation Program of the Chinese Academy of Sciences. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:88909			Serial	1717
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	Author	Pogosov, W.V.; Zhao, H.J.; Misko, V.R.; Peeters, F.M.
	Title	Kink-antikink vortex transfer in periodic-plus-random pinning potential : theoretical analysis and numerical experiments			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	2	Pages
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The influence of random pinning on the vortex dynamics in a periodic square potential under an external drive is investigated. Using numerical experiments and theoretical approach, we found several dynamical regimes of vortex motion that are different from the ones for a regular pinning potential. Vortex transfer is controlled by kinks and antikinks, which either pre-exist in the system or appear spontaneously in pairs and then propagate. When kinks and antikinks collide, they annihilate. We provide clear physical interpretations of the observed features.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000274002100087	Publication Date	2010-01-19
	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	10	Open Access
	Notes	; This work was supported by the “Odysseus” Program of the Flemish government, FWO-Vl, and IAP. W.V.P. acknowledges support from RFBR (Contract No. 09-02-00248). ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:81251			Serial	1761
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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	Yang, C.H.; Peeters, F.M.; Xu, W.
	Title	Landau-level broadening due to electron-impurity interaction in graphene in strong magnetic fields			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	7	Pages	075401:1-075401:6
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The effect of electron-impurity and electron-electron interactions on the energy spectrum of electrons moving in graphene is investigated in the presence of a high magnetic field. We find that the width of the broadened Landau levels exhibits an approximate 1/B dependence near half filling for charged impurity scattering. The Landau-level width, the density of states, and the Fermi energy exhibit an oscillatory behavior as a function of magnetic field. Comparison with experiment shows that scattering with charged impurities cannot be the main scattering mechanism that determines the width of the Landau levels.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000280553700008	Publication Date	2010-08-04
	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	38	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the National Science Foundation of China under Grant No. 10804053, the Foundation of NUIST under Grant No. S8108062001, and the Chinese Academy of Sciences and Department of Science and Technology of Yunnan Province. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:84043			Serial	1769
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	Author	Bousige, C.; Rols, S.; Cambedouzou, J.; Verberck, B.; Pekker, S.; Kováts, É.; Durkó, G.; Jalsovsky, I.; Pellegrini, É.; Launois, P.
	Title	Lattice dynamics of a rotor-stator molecular crystal: Fullerene-cubane C₆₀\centerdot C₈H₈			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	19	Pages	195413-195413,10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The dynamics of fullerene-cubane (C60⋅C8H8) cocrystal is studied combining experimental [x-ray diffuse scattering, quasielastic and inelastic neutron scattering (INS)] and simulation (molecular dynamics) investigations. Neutron scattering gives direct evidence of the free rotation of fullerenes and of the libration of cubanes in the high-temperature phase, validating the rotor-stator description of this molecular system. X-ray diffuse scattering shows that orientational disorder survives the order/disorder transition in the low-temperature phase, although the loss of fullerene isotropic rotational diffusion is featured by the appearance of a 2.2 meV mode in the INS spectra. The coupling between INS and simulations allows identifying a degeneracy lift of the cubane librations in the low temperature phase, which is used as a tool for probing the environment of cubane in this phase and for getting further insights into the phase transition mechanism.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000283923500004	Publication Date	2010-11-08
	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	16	Open Access
	Notes	; The authors acknowledge P.-A. Albouy and S. Rouziere (LPS, Orsay) for fruitful discussions and for their support during diffuse scattering experiments. Work in Hungary was supported by the Hungarian Research Fund, OTKA under Grant No. K72954. The CS group at the ILL is acknowledged for their support during the MD simulations. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:85801			Serial	1802
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	Author	Neek-Amal, M.; Peeters, F.M.
	Title	Linear reduction of stiffness and vibration frequencies in defected circular monolayer graphene			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	23	Pages	11
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000279336000001	Publication Date	2010-06-29
	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	44	Open Access
	Notes	; Financial support was provided by the Hungarian Research Foundation (Contracts No. OTKA K68312, No. K77771, No. K73361, and No. F68726). ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:83857			Serial	1820
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	Author	Tsvyashchenko, A.V.; Nikolaev, A.V.; Velichkov, A.I.; Salamatin, A.V.; Fomicheva, L.N.; Ryasny, G.K.; Sorokin, A.A.; Kochetov, O.I.; Budzynski, M.; Michel, K.H.
	Title	Lowering of the spatial symmetry at the gamma ->alpha phase transition in cerium			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	9	Pages	1-4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using time-differential perturbed angular correlation spectroscopy we have measured the electric field gradient (EFG) at 111Cd probe nuclei in solid Ce in a pressure range up to 8 GPa. Covering various allotropic phases of Ce, we find that the value of the EFG in the cubic α phase is almost four times larger than in the cubic γ phase and close to values in the noncubic phases α′ and α″. These results together with the differences in time modulation of the spectra are interpreted as evidence for quadrupolar electronic charge-density ordering and symmetry lowering at the γ→α transition while the lattice remains face-centered cubic
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000282004400001	Publication Date	2010-09-16
	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	11	Open Access
	Notes	; This work is supported by the Program of the Presidium of the Russian Academy of Sciences “Physics of Strongly Compressed Matter.” We are grateful to S. M. Stishov, B. Verberck, A. N. Grum-Grzhimailo, V. B. Brudanin and G. Heger for support of this work and discussion of the results. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:85464			Serial	1854
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	Author	Maignan, A.; Lebedev, O.I.; Van Tendeloo, G.; Martin, C.; Hebert, S.
	Title	Metal to insulator transition in the n-type hollandite vanadate Pb_1.6V₈O₁₆			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	3	Pages	035122, 1-035122,5
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The transport and magnetic measurements of polycrystalline Pb1.6V8O16 hollandite reveal a concomitant metal to insulator and antiferromagnetic transition at TMI≈140 K. A clear localization is found below TMI, evidenced by a rapid increase in the absolute value of the negative Seebeck coefficient. The structural study by x-ray and transmission electron microscopy confirms the hollandite structure and shows that no structural transition occurs at TMI, ruling out a possible charge orbital ordering. The negative Seebeck coefficient observed from 50 K up to 900 K, with values reaching S=−38 μV K−1 at 900 K, is explained by the electron doping of ∼1.4e− in the V empty t2g orbitals responsible for the bad metal resistivity (ρ900 K∼2 mΩ cm). As this S value is close to that obtained by considering only the spin and orbital degeneracies, it is expected that \|S\| for such vanadates will not be sensitive at high temperature to the t2g band filling
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000280366300002	Publication Date	2010-07-27
	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	10	Open Access
	Notes				Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:84065			Serial	2009
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	Author	Zhang, L.; Turner, S.; Brosens, F.; Verbeeck, J.
	Title	Model-based determination of dielectric function by STEM low-loss EELS			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	3	Pages	035102
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Theory of quantum systems and complex systems
	Abstract	Dielectric properties of materials are crucial in describing the electromagnetic response of materials. As devices are becoming considerably smaller than the optical wavelength, the conventional measuring methods based on optical response are limited by their spatial resolution. Electron energy loss spectroscopy performed in a scanning transmission electron microscope is a good alternative to obtain the dielectric properties with excellent spatial resolution. Due to the overlap of diffraction discs in scanning transmission electron microscopy, it is difficult to apply conventional experimental settings to suppress retardation losses. In this contribution, a relativistic dielectric model for the loss function is presented which is used in a model based optimization scheme to estimate the complex dielectric function of a material. The method is applied to experiments on bulk diamond and SrTiO3 and shows a good agreement with optical reference data when retardation effects are included. Application of this technique to nanoparticles is possible but several theoretical assumptions made in the model of the loss function are violated and interpretation becomes problematic.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000274002300027	Publication Date	2010-01-08
	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	9	Open Access
	Notes	Esteem – 026019; Fwo			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:81258UA @ admin @ c:irua:81258			Serial	2098
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	Author	Jorissen, K.; Rehr, J.J.; Verbeeck, J.
	Title	Multiple scattering calculations of relativistic electron energy loss spectra			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	15	Pages	155108,1-155108,6
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A generalization of the real-space Greens-function approach is presented for ab initio calculations of relativistic electron energy loss spectra (EELS) which are particularly important in anisotropic materials. The approach incorporates relativistic effects in terms of the transition tensor within the dipole-selection rule. In particular, the method accounts for relativistic corrections to the magic angle in orientation resolved EELS experiments. The approach is validated by a study of the graphite C K edge, for which we present an accurate magic angle measurement consistent with the predicted value.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000277210500038	Publication Date	2010-04-13
	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	24	Open Access
	Notes	Fwo; Esteem 026019			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:82805UA @ admin @ c:irua:82805			Serial	2230
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	Author	Neek-Amal, M.; Peeters, F.M.
	Title	Nanoindentation of a circular sheet of bilayer graphene			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	23	Pages	235421,1-235421,6
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Nanoindentation of bilayer graphene is studied using molecular-dynamics simulations. We compared our simulation results with those from elasticity theory as based on the nonlinear Föppl-Hencky equations with rigid boundary condition. The force-deflection values of bilayer graphene are compared to those of monolayer graphene. Youngs modulus of bilayer graphene is estimated to be 0.8 TPa which is close to the value for graphite. Moreover, an almost flat bilayer membrane at low temperature under central load has a 14% smaller Youngs modulus as compared to the one at room temperature.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000278710800003	Publication Date	2010-06-11
	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	108	Open Access
	Notes	; We gratefully acknowledge comments from R. Asgari. M.N.-A. would like to thank the Universiteit of Antwerpen for its hospitality where part of this work was performed. This work was supported by the Flemish science foundation (FWO-V1) and the Belgium Science Policy (IAP). ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:83093			Serial	2259
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	Author	Xu, W.; Dong, H.M.; Li, L.L.; Yao, J.Q.; Vasilopoulos, P.; Peeters, F.M.
	Title	Optoelectronic properties of graphene in the presence of optical phonon scattering			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	12	Pages	125304-125304,9
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study in detail the optoelectronic properties of graphene. Considering the electron interactions with photons and phonons, we employ the mass- and energy-balance equations to self-consistently evaluate the photoinduced carrier densities, the optical conductance, and the transmission coefficient in the presence of a linearly polarized radiation field. We demonstrate that the photoinduced carrier densities increase around the electron-photon-phonon resonant transition. They depend strongly on the radiation intensity and frequency, temperature, and dark carrier density. For short-wavelength radiation (L<3 μm), we obtain the universal optical conductance σ0=e2/(4ℏ). Importantly, there exists an optical-absorption window in the radiation wavelength range 4100 μm, which is induced by different transition energies required for interband and intraband optical absorption. The position and width of this window depend sensitively on the temperature and the carrier density of the system. These theoretical results are in line with recent experimental findings and indicate that graphene exhibits important features not only in the visible regime but also in the midinfrared bandwidth.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000281516500009	Publication Date	2010-09-03
	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	28	Open Access
	Notes	; This work was supported by the Chinese Academy of Sciences, National Natural Science Foundation of China, and Department of Science and Technology of Yunnan Province. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:84260			Serial	2496
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	Author	Zha, G.-Q.; Covaci, L.; Zhou, S.-P.; Peeters, F.M.
	Title	Proximity-induced pseudogap in mesoscopic superconductor/normal-metal bilayers			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	14	Pages	140502-140502,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Recent scanning tunneling microscopy (STM) measurements of the proximity effect in Au/La2−xSrxCuO4 and La1.55Sr0.45CuO4/La2−xSrxCuO4 bilayers showed a proximity-induced pseudogap [O. Yuli, I. Asulin, Y. Kalcheim, G. Koren, and O. Millo, Phys. Rev. Lett. 103, 197003 (2009)]. We describe the proximity effect in mesoscopic superconductor/normal-metal bilayers by using the Bogoliubov-de Gennes equations for a tight-binding Hamiltonian with competing antiferromagnetic and d-wave superconductivity orders. The temperature-dependent local density of states is calculated as a function of the distance from the interface. Bound state due to both d-wave and spin-density wave gaps are formed in the normal metal for energies less than the respective gaps. If there is a mismatch between the Fermi velocities in the two layers we observe that these states will shift in energy when spin-density wave order is present, thus inducing a minigap at finite energy. We conclude that the STM measurement in the proximity structures is able to distinguish between the two scenarios proposed for the pseudogap (competing or precursor to superconductivity).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000282507200002	Publication Date	2010-10-05
	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 Flemish Science Foundation (FWO-Vl), by Belgian Science Policy (IAP), by National Natural Science Foundation of China under Grants No. 10904089 and No. 60971053, by the Research Fund of Higher Education of China under Grant No. 20093108120005, by Shanghai Leading Academic Discipline project under Grant No. S30105, by Science and Technology Committee of Shanghai Municipal under Grant No. 09JC1406000, by Shanghai Municipal Education Committee under Grants No. shu-08053 and No. 10zz63, and by Innovation Funds of Shanghai University. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:85028			Serial	2735
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	Author	Schattschneider, P.; Verbeeck, J.; Mauchamp, V.; Jaouen, M.; Hamon, A.-L.
	Title	Real-space simulations of spin-polarized electronic transitions in iron			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	14	Pages	144418-144418,11
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	After the advent of energy-loss magnetic chiral dichroism (EMCD) in 2006, rapid progress in theoretical understanding and in experimental performance was achieved, recently demonstrating a spatial resolution of better than 2 nm. Similar to the x-ray magnetic circular dichroism technique, EMCD is used to study atom specific magnetic moments. The latest generation of electron microscopes opens the road to the mapping of spin moments on the atomic scale with this method. Here the theoretical background to reach this challenging aim is elaborated. Numerical simulations of the L3 transition in an Fe specimen, based on a combination of the density-matrix approach for inelastic electron scattering with the propagation of the probe electron in the lattice potential indicate the feasibility of single spin mapping in the electron microscope.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000282678900006	Publication Date	2010-10-08
	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	11	Open Access
	Notes	P.S. acknowledges the support of the Austrian Science Fund, Project No. I543-N20.			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:85029UA @ admin @ c:irua:85029			Serial	2832
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	Author	Xu, B.; Milošević, M.V.; Peeters, F.M.
	Title	Second-order multiple-quanta flux entry into a perforated spherical mesoscopic superconductor			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	21	Pages	214501-214501,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Flux entry in type-II superconductors without prominent symmetry is a first-order phase transition, where flux enters conventionally gradual in units of a flux quantum. Here we show that neither is necessarily the case in a mesoscopic superconducting sphere with a perforation. In axially applied magnetic field, vortices initially occupy the hole, and can oppose further flux entry in the sample. As a result, multiple-quanta flux entry is found at significantly higher field, and it can manifest as a second-order transition due to suppressed geometric barrier at the equatorial belt of the sample. At high fields a new state is found, with gradually destroyed condensate from the equator inwards, the exact opposite of surface superconductivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000286737800007	Publication Date	2010-12-02
	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	2	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-V1), the Belgian Science Policy (IAP), and the ESF “Nanoscience and Engineering in Superconductivity” program. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:88039			Serial	2957
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	Author	Zarenia, M.; Pereira, J.M.; Chaves, A.; Peeters, F.M.; Farias, G.A.
	Title	Simplified model for the energy levels of quantum rings in single layer and bilayer graphene			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	4	Pages	045431,1-045431,9
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Within a minimal model, we present analytical expressions for the eigenstates and eigenvalues of carriers confined in quantum rings in monolayer and bilayer graphene. The calculations were performed in the context of the continuum model by solving the Dirac equation for a zero width ring geometry, i.e., by freezing out the carrier radial motion. We include the effect of an external magnetic field and show the appearance of Aharonov-Bohm oscillations and of a nonzero gap in the spectrum. Our minimal model gives insight on the energy spectrum of graphene-based quantum rings and models different aspects of finite width rings.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000277186000010	Publication Date	2010-01-29
	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	76	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the Bilateral program between Flanders and Brazil, and the Brazilian Council for Research (CNPq). ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:82866			Serial	3005
Permanent link to this record



	Author	Földi, P.; Szaszkó-Bogár, V.; Peeters, F.M.
	Title	Spin-orbit interaction controlled properties of two-dimensional superlattices			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	11	Pages	115302-115302,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The band structure of two-dimensional artificial superlattices in the presence of (Rashba-type) spin-orbit interaction (SOI) is presented. The position and shape of the energy bands in these spintronic crystals depend on the geometry as well as the strength of the SOI, which can be tuned by external gate voltages. For finite mesoscopic arrays, we show that their conductance properties and possible applications can be understood from these spin-dependent band diagrams.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000281516300005	Publication Date	2010-09-03
	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	6	Open Access
	Notes	; We thank M. G. Benedict and F. Bartha for useful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP) and the Hungarian Scientific Research Fund (OTKA) under Contracts No. T81364 and No. M045596. P.F. was supported by a J. Bolyai grant of the Hungarian Academy of Sciences. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:84259			Serial	3092
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	Author	Avetisyan, A.A.; Partoens, B.; Peeters, F.M.
	Title	Stacking order dependent electric field tuning of the band gap in graphene multilayers			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	11	Pages	115432,1-115432,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The effect of different stacking order of graphene multilayers on the electric field induced band gap is investigated. We considered a positively charged top and a negatively charged back gate in order to independently tune the band gap and the Fermi energy of three and four layer graphene systems. A tight-binding approach within a self-consistent Hartree approximation is used to calculate the induced charges on the different graphene layers. We found that the gap for trilayer graphene with the ABC stacking is much larger than the corresponding gap for the ABA trilayer. Also we predict that for four layers of graphene the energy gap strongly depends on the choice of stacking, and we found that the gap for the different types of stacking is much larger as compared to the case of Bernal stacking. Trigonal warping changes the size of the induced electronic gap by approximately 30% for intermediate and large values of the induced electron density.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000276248800145	Publication Date	2010-03-19
	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	142	Open Access
	Notes	; ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:82274			Serial	3148
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	Author	Vodolazov, D.Y.; Peeters, F.M.
	Title	Strong influence of nonlocal nonequilibrium effects on the dynamics of the order parameter in a phase-slip center: ring studies			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	18	Pages	184521,1-184521,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study the influence of the inelastic relaxation time τ̃E of the quasiparticle distribution function f(E) on the phase slip process in quasi-one-dimensional superconducting rings at a temperature close to the critical temperature Tc. We find that the initial time of growth of the order parameter \|Δ\| in the phase slip core after the phase slip is a nonmonotonic function of τ̃E which has a maximum at τ̃E≃τ̃GL=πℏ/8kB(Tc−T) and has a tendency to saturate for large τ̃E⪢τ̃GL. The effective heating of the electron subsystem due to the increase in \|Δ\| in the phase slip center together with the above effect result in a nonmonotonic dependence of the number of subsequent phase slips on τ̃E in rings of relatively large radius (in which each phase slip reduces the current density to a small fraction of its initial value). During the phase slip process the order parameter distribution has two peaks near the phase slip core due to the diffusion of the nonequilibrium quasiparticles from that region.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000278141800100	Publication Date	2010-05-19
	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	5	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). D.Y.V. also acknowledges support from the Russian Foundation for Basic Research, Federal Target Programme “Scientific and scientific-pedagogical personnel of innovative Russia in 2009-2013” and Dynasty Foundation. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:83305			Serial	3182
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	Author	Branchaud, S.; Kam, A.; Zawadzki, P.; Peeters, F.M.; Sachrajda, A.S.
	Title	Transport detection of quantum Hall fluctuations in graphene			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	12	Pages	121406,1-121406,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Low-temperature magnetoconductance measurements were made in the vicinity of the charge neutrality point (CNP). Two origins for the fluctuations were identified close to the CNP. At very low magnetic fields there exist only mesoscopic magnetoconductance quantum interference features which develop rapidly as a function of density. At slightly higher fields (>0.5 T), close to the CNP, additional fluctuations track the quantum Hall (QH) sequence expected for monolayer graphene. These additional features are attributed to effects of locally charging individual QH localized states. These effects reveal a precursor to the quantum Hall effect since, unlike previous transport observations of QH dot charging effects, they occur in the absence of quantum Hall plateaus or Shubnikov-de Haas oscillations. From our transport data we are able to extract parameters that characterize the inhomogeneities in our device.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000276248900026	Publication Date	2010-03-09
	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	25	Open Access
	Notes	; We would like to acknowledge important motivating discussions with Louis Gaudreau, Ghislain Granger, Pawel Hawrylak, Devrim Guclu, Josh Folk, and Mark Lundeberg. A. S. S. and F. M. P. acknowledge funding from CIFAR. A. S. S. and S. B. acknowledge assistance from NSERC. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:82275			Serial	3723
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	Author	Liu, Y.; Cheng, F.; Li, X.J.; Peeters, F.M.; Chang, K.
	Title	Tuning of the two electron states in quantum rings through the spin-orbit interaction			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	4	Pages	1-7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The effect of the Coulomb interaction on the energy spectrum and anisotropic distribution of two electron states in a quantum ring in the presence of Rashba spin-orbit interaction (RSOI) and Dresselhaus SOI (DSOI) is investigated in the presence of a perpendicular magnetic field. We find that the interplay between the RSOI and DSOI makes the single quantum ring behaves like a laterally coupled quantum dot and the interdot coupling can be tuned by changing the strengths of the SOIs. The interplay can lead to singlet-triplet state mixing and anticrossing behavior when the singlet and triplet states meet with increasing magnetic field. The two electron ground state displays a bar-bell-like spatial anisotropic distribution in a quantum ring at a specific crystallographic direction, i.e., [110] or [11̅ 0], which can be switched by reversing the direction of the perpendicular electric field. The ground state exhibits a singlet-triplet state transition with increasing magnetic field and strengths of RSOI and DSOI. An anisotropic electron distribution is predicted which can be detected through the measurement of its optical properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000280234100006	Publication Date	2010-07-22
	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 NSFC under Grants No. 60525405 and No. 10874175 and the Belgium Science Policy (IAP). ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:84087			Serial	3756
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	Author	van den Heuvel, W.; Tikhomirov, V.K.; Kirilenko, D.; Schildermans, N.; Chibotaru, L.F.; Vanacken, J.; Gredin, P.; Mortier, M.; Van Tendeloo, G.; Moshchalkov, V.V.
	Title	Ultralow blocking temperature and breakdown of the giant spin model in Er³⁺-doped nanoparticles			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	9	Pages	094421-094421,8
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The magnetization of luminescent Er3+-doped PbF2 nanoparticles (formula Er0.3Pb0.7F2.3) has been studied. Despite the high concentration of the doping Er3+ ions and relatively large size (8 nm) of these nanoparticles we have found no deviation between field-cooled and zero-field-cooled magnetization curves down to T=0.35 K, which points out an ultralow blocking temperature for the reversal of magnetization. We also have found strongly deviating magnetization curves M(H/T) for different temperatures T. These results altogether show that the investigated nanoparticles are not superparamagnetic, but rather each Er3+ ion in these nanoparticles is found in a paramagnetic state down to very low temperatures, which implies the breakdown of the Néel-Brown giant spin model in the case of these nanoparticles. Calculations of magnetization within a paramagnetic model of noninteracting Er3+ ions completely support this conclusion. Due to the ultralow blocking temperature, these nanoparticles have a potential for magnetic field-induced nanoscale refrigeration with an option of their optical localization and temperature control.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000281773300005	Publication Date	2010-09-13
	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	11	Open Access
	Notes	Fwo			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:85423			Serial	3796
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	Author	Geurts, R.; Milošević, M.V.; Peeters, F.M.
	Title	Vortex matter in mesoscopic two-gap superconducting disks: influence of Josephson and magnetic coupling			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	21	Pages	15
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000278846600001	Publication Date	2010-06-21
	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	89	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen), the Belgian Science Policy (IAP), the ESF “Nanoscience and Engineering in Superconductivity” (NES) program, and the ESF “Arrays of Quantum Dots and Josephson Junctions” network. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:83933			Serial	3872
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	Author	Doria, M.M.; Romaguera, A.R. de C.; Peeters, F.M.
	Title	Vortex patterns in a mesoscopic superconducting rod with a magnetic dot			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	10	Pages	104529,1-104529,11
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study a mesoscopic superconducting rod with a magnetic dot on its top having its moment oriented along the axis of symmetry. We study the dependence of the vortex pattern with the height and find that for very short and very long rods, the vortex pattern acquires a simple structure, consisting of giant and of multivortex states, respectively. In the long limit, the most stable configuration consists of two vortices, that reach the lateral surface of the rod diametrically opposed. The long rod shows reentrant behavior within some range of its radius and of the dots magnetic moment. Our results are obtained within the Ginzburg-Landau approach in the limit of no magnetic shielding.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000276248700123	Publication Date	2010-03-31
	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	5	Open Access
	Notes	; The three authors acknowledge CNPq and the bilateral program between Brazil and Flanders for financial support. They also make the following acknowledgments for financial support: A. R. de C. Romaguera to FACEPE, M. M. Doria to FAPERJ, and F. M. Peeters to the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IUAP), and the ESF-AQDJJ network. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:82272			Serial	3877
Permanent link to this record



	Author	Berdiyorov, G.R.; Milošević, M.V.; Peeters, F.M.
	Title	Vortices induced in a superconducting loop by asymmetric kinetic inductance and their detection in transport measurements			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	81	Issue	14	Pages	144511,1-144511,5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using time-dependent Ginzburg-Landau theory, we study the dynamic properties of a rectangular superconducting loop, which are found to depend on the position of the current leads. For asymmetric positioning of the leads, different kinetic inductance of the two paths for injected electric current leads to different critical conditions in the two branches. System self-regulates by allowing vortex entry, as vortex currents bring equilibration between the two current flows and the conventional resistive state can be realized. We also demonstrate that individual vortex entry in the loop can be detected by measuring the voltage between normal-metal leads, for applied currents comparable in magnitude to the screening currents.
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000277210200107	Publication Date	2010-04-21
	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	18	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the ESF-NES program, and the ESF-AQDJJ network. G.R.B. acknowledges support from FWO-Vlaanderen. The authors thank S. Michotte for useful discussions. ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:82804			Serial	3901
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