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“Defect controlled room temperature ferromagnetism in Co-doped barium titanate nanocrystals”. Ray S, Kolen'ko YV, Kovnir KA, Lebedev OI, Turner S, Chakraborty T, Erni R, Watanabe T, Van Tendeloo G, Yoshimura M, Itoh M, Nanotechnology 23, 025702 (2012). http://doi.org/10.1088/0957-4484/23/2/025702
Abstract: Defect mediated high temperature ferromagnetism in oxide nanocrystallites is the central feature of this work. Here, we report the development of room temperature ferromagnetism in nanosized Co-doped barium titanate particles with a size of around 14 nm, synthesized by a solvothermal drying method. A combination of x-ray diffraction with state-of-the-art electron microscopy techniques confirms the intrinsic doping of Co into BaTiO3. The development of the room temperature ferromagnetism was tracked down to the different donor defects, namely hydroxyl groups at the oxygen site (\mathrm {OH}\mathrm {(O)}
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 19
DOI: 10.1088/0957-4484/23/2/025702
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“Structure and defect characterization of multiferroic <tex>ReMnO$3 films and multilayers by TEM”. Jehanathan N, Lebedev O, Gélard I, Dubourdieu C, Van Tendeloo G, Nanotechnology 21, 075705 (2010). http://doi.org/10.1088/0957-4484/21/7/075705
Abstract: Epitaxial rare earth manganite thin films (ReMnO3; Re = Tb, Ho, Er, and Y) and multilayers were grown by liquid injection metal organic chemical vapor deposition (MOCVD) on YSZ(111) and the same systems were grown c-oriented on Pt(111) buffered Si substrates. They have been structurally investigated by electron diffraction (ED) and high resolution transmission electron microscopy (HRTEM). Nanodomains of secondary orientation are observed in the hexagonal YMnO3 films. They are related to a YSZ(111) and Pt(111) misorientation. The epitaxial film thickness has an influence on the defect formation. TbO2 and Er2O3 inclusions are observed in the TbMnO3 and ErMnO3 films respectively. The structure and orientation of these inclusions are correlated to the resembling symmetry and structure of film and substrate. The type of defect formed in the YMnO3/HoMnO3 and YMnO3/ErMnO3 multilayers is also influenced by the type of substrate they are grown on. In our work, atomic growth models for the interface between the film/substrate are proposed and verified by comparison with observed and computer simulated images.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 15
DOI: 10.1088/0957-4484/21/7/075705
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“Quantum tunneling through graphene nanorings”. Wu Z, Zhang ZZ, Chang K, Peeters FM, Nanotechnology 21, 185201 (2010). http://doi.org/10.1088/0957-4484/21/18/185201
Abstract: We investigate theoretically quantum transport through graphene nanorings in the presence of a perpendicular magnetic field. Our theoretical results demonstrate that the graphene nanorings behave like a resonant tunneling device, contrary to the Aharonov-Bohm oscillations found in conventional semiconductor rings. The resonant tunneling can be tuned by the Fermi energy, the size of the central part of the graphene nanorings and the external magnetic field.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.44
Times cited: 34
DOI: 10.1088/0957-4484/21/18/185201
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“Resonant tunneling through S- and U-shaped graphene nanoribbons”. Zhang ZZ, Wu ZH, Chang K, Peeters FM, Nanotechnology 20, 415203 (2009). http://doi.org/10.1088/0957-4484/20/41/415203
Abstract: We theoretically investigate resonant tunneling through S- and U-shaped nanostructured graphene nanoribbons. A rich structure of resonant tunneling peaks is found emanating from different quasi-bound states in the middle region. The tunneling current can be turned on and off by varying the Fermi energy. Tunability of resonant tunneling is realized by changing the width of the left and/or right leads and without the use of any external gates.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.44
Times cited: 32
DOI: 10.1088/0957-4484/20/41/415203
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“Crystallographic plane tuning of charge and spin transport in semiconductor quantum wires”. Wang M, Chang K, Wang LG, Dai N, Peeters FM, Nanotechnology 20, 365202 (2009). http://doi.org/10.1088/0957-4484/20/36/365202
Abstract: We investigate theoretically the charge and spin transport in quantum wires grown along different crystallographic planes in the presence of the Rashba spinorbit interaction (RSOI) and the Dresselhaus spinorbit interaction (DSOI). We find that changing the crystallographic planes leads to a variation of the anisotropy of the conductance due to a different interplay between the RSOI and DSOI, since the DSOI is induced by bulk inversion asymmetry, which is determined by crystallographic plane. This interplay depends sensitively on the crystallographic planes, and consequently leads to the anisotropic charge and spin transport in quantum wires embedded in different crystallographic planes.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.44
Times cited: 14
DOI: 10.1088/0957-4484/20/36/365202
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“Effects of lateral asymmetry on electronic structure of strained semiconductor nanorings in a magnetic field”. Milošević, MM, Tadić, M, Peeters FM, Nanotechnology 19 (2008). http://doi.org/10.1088/0957-4484/19/45/455401
Abstract: The influence of lateral asymmetry on the electronic structure and optical transitions in elliptical strained InAs nanorings is analyzed in the presence of a perpendicular magnetic field. Two-dimensional rings are assumed to have elliptical inner and outer boundaries oriented in mutually orthogonal directions. The influence of the eccentricity of the ring on the energy levels is analyzed. For large eccentricity of the ring, we do not find any AharonovBohm effect, in contrast to circular rings. Rather, the single-particle states of the electrons and the holes are localized as in two laterally coupled quantum dots formed in the lobes of the nanoring. Our work indicates that the control of shape is important for the existence of the AharonovBohm effect in semiconductor nanorings.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.44
Times cited: 11
DOI: 10.1088/0957-4484/19/45/455401
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“Surface enhanced Raman scattering of silver sensitized cobalt nanoparticles in metaldielectric nanocomposites”. Margueritat J, Gonzalo J, Afonso CN, Hörmann U, Van Tendeloo G, Mlayah A, Murray DB, Saviot L, Zhou Y, Hong MH, Luk'yanchuk BS, Nanotechnology 19, 375701 (2008). http://doi.org/10.1088/0957-4484/19/37/375701
Abstract: We report the preparation of a new type of nanocomposite containing cobalt and silver nanoparticles organized in parallel layers with a well controlled separation. This arrangement allows the observation of an enhanced low-frequency Raman signal at the vibration frequency of cobalt nanoparticles excited through the surface plasmons of silver nanoparticles. Numerical simulations of the electric field confirm the emergence of hot spots when the separation between silver and cobalt nanoparticles is small enough.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 11
DOI: 10.1088/0957-4484/19/37/375701
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“Carbon nanotube TiO2 hybrid films for detecting traces of O2”. Llobet E, Espinosa EH, Sotter E, Ionescu R, Vilanova X, Torres J, Felten A, Pireaux JJ, Ke X, Van Tendeloo G, Renaux F, Paint Y, Hecq M, Bittencourt C;, Nanotechnology 19, 375501 (2008). http://doi.org/10.1088/0957-4484/19/37/375501
Abstract: Hybrid titania films have been prepared using an adapted sol-gel method for obtaining well-dispersed hydrogen plasma-treated multiwall carbon nanotubes in either pure titania or Nb-doped titania. The drop-coating method has been used to fabricate resistive oxygen sensors based on titania or on titania and carbon nanotube hybrids. Morphology and composition studies have revealed that the dispersion of low amounts of carbon nanotubes within the titania matrix does not significantly alter its crystallization behaviour. The gas sensitivity studies performed on the different samples have shown that the hybrid layers based on titania and carbon nanotubes possess an unprecedented responsiveness towards oxygen (i.e. more than four times higher than that shown by optimized Nb-doped TiO(2) films). Furthermore, hybrid sensors containing carbon nanotubes respond at significantly lower operating temperatures than their non-hybrid counterparts. These new hybrid sensors show a strong potential for monitoring traces of oxygen (i.e. <= 10 ppm) in a flow of CO(2), which is of interest for the beverage industry.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 48
DOI: 10.1088/0957-4484/19/37/375501
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“Synthesis of few-layer graphene via microwave plasma-enhanced chemical vapour deposition”. Malesevic A, Vitchev R, Schouteden K, Volodin A, Zhang L, Van Tendeloo G, Vanhulsel A, van Haesendonck C, Nanotechnology 19, 305604 (2008). http://doi.org/10.1088/0957-4484/19/30/305604
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 309
DOI: 10.1088/0957-4484/19/30/305604
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“Structural and luminescence investigation on gadolinium gallium garnet nanocrystalline powders prepared by solution combustion synthesis”. Krsmanovic R, Morozov VA, Lebedev OI, Polizzi S, Speghini A, Bettinelli M, Van Tendeloo G, Nanotechnology 18, 325604 (2007). http://doi.org/10.1088/0957-4484/18/32/325604
Abstract: Nanocrystalline powders of undoped and lanthanide (Pr3+, Tm3+)- doped gadolinium gallium garnet, Gd3Ga5O12 (GGG), were prepared by propellant synthesis and studied by x-ray powder diffraction (XRD), electron diffraction (ED), high-resolution electron microscopy (HREM) and luminescence spectroscopy. The x-ray diffraction patterns of the GGG samples were analysed using the Rietveld method. The Rietveld refinement reveals the existence of two garnet-type phases: both are cubic (space group Ia $(3) over bar $d) with a slightly different lattice parameter and probably a slightly different composition. Electron diffraction and electron microscopy measurements confirm the x-ray diffraction results. EDX measurements for lanthanide-doped samples show that stable solid solutions with composition Gd(3-x)Ln(x)Ga(5)O(12), x approximate to 0.3 ( Ln = Pr; Tm) have been obtained. The luminescence properties of the Tm3+ -doped nanocrystalline GGG samples were measured and analysed.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 33
DOI: 10.1088/0957-4484/18/32/325604
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“CdSe quantum dot formation: alternative paths to relaxation of a strained CdSe layer and influence of the capping conditions”. Robin I-C, Aichele T, Bougerol C, André, R, Tatarenko S, Bellet-Amalric E, van Daele B, Van Tendeloo G, Nanotechnology 18, 265701 (2007). http://doi.org/10.1088/0957-4484/18/26/265701
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 8
DOI: 10.1088/0957-4484/18/26/265701
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“Structural characterization and luminescence properties of nanostructured lanthanide-doped Sc2O3 prepared by propellant synthesis”. Krsmanovic R, Lebedev OI, Speghini A, Bettinelli M, Polizzi S, Van Tendeloo G, Nanotechnology 17, 2805 (2006). http://doi.org/10.1088/0957-4484/17/11/013
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 22
DOI: 10.1088/0957-4484/17/11/013
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“Controllable synthesis of novel one-dimensional carbon nanomaterials on an alkali-element-modified Cu catalyst”. Tao XY, Zhang XB, Cheng J-P, Liu F, Li Y, Van Tendeloo G, Nanotechnology 17, 224 (2006). http://doi.org/10.1088/0957-4484/17/1/037
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 4
DOI: 10.1088/0957-4484/17/1/037
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“Preparation and structure analysis of Gd(OH)3 nanorods”. Du G, Van Tendeloo G, Nanotechnology 16, 595 (2005). http://doi.org/10.1088/0957-4484/16/4/043
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.44
Times cited: 28
DOI: 10.1088/0957-4484/16/4/043
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“Transport of magnetic edge states in a quantum wire exposed to a non-homogeneous magnetic field”. Badalyan SM, Peeters FM, Nanotechnology 12, 570 (2001). http://doi.org/10.1088/0957-4484/12/4/340
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.44
Times cited: 5
DOI: 10.1088/0957-4484/12/4/340
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“The polaron-bipolaron transition for acoustical three-dimensional polarons”. da Costa WB, Peeters FM, Journal of physics : condensed matter 8, 2173 (1996). http://doi.org/10.1088/0953-8984/8/13/009
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.346
Times cited: 10
DOI: 10.1088/0953-8984/8/13/009
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“Diagonalization of the generalized Feynman bipolaron model in a magnetic field”. da Costa WB, Peeters FM, Journal of physics : condensed matter 7, 1293 (1995). http://doi.org/10.1088/0953-8984/7/7/011
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.346
Times cited: 18
DOI: 10.1088/0953-8984/7/7/011
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“Renormalized perturbation series for quantum dots”. Matulis A, Peeters FM, Journal of physics : condensed matter 6, 7751 (1994). http://doi.org/10.1088/0953-8984/6/38/013
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.346
Times cited: 77
DOI: 10.1088/0953-8984/6/38/013
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“Neutron and X-ray-scattering cross sections of orientationally disordered solid C60”. Copley JRD, Michel KH, Journal of physics : condensed matter 5, 4353 (1993). http://doi.org/10.1088/0953-8984/5/26/008
Abstract: Differential cross sections for neutron and x-ray scattering have been derived for the orientationally disordered phase of solid C60. Interaction centres are placed at nuclei and at the centres of interatomic bonds. Bragg and diffuse scattering cross sections, for single crystals and for powders, are formulated using symmetry-adapted rotator functions. Thermal averages are calculated taking account of crystal field effects. Thermally averaged orientational distribution functions have also been calculated.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.346
Times cited: 34
DOI: 10.1088/0953-8984/5/26/008
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“The work function of few-layer graphene”. Leenaerts O, Partoens B, Peeters FM, Volodin A, van Haesendonck C, Journal of physics : condensed matter 29, 035003 (2017). http://doi.org/10.1088/0953-8984/29/3/035003
Abstract: A theoretical and experimental study of the work function of few-layer graphene is reported. The influence of the number of layers on the work function is investigated in the presence of a substrate, a molecular dipole layer, and combinations of the two. The work function of few-layer graphene is almost independent of the number of layers with only a difference between monolayer and multilayer graphene of about 60 meV. In the presence of a charge-donating substrate the charge distribution is found to decay exponentially away from the substrate and this is directly reflected in the work function of few-layer graphene. A dipole layer changes the work function only when placed in between the substrate and few-layer graphene through a change of the charge transfer between the two.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Times cited: 61
DOI: 10.1088/0953-8984/29/3/035003
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“Validity criteria for Fermi's golden rule scattering rates applied to metallic nanowires”. Moors K, Sorée B, Magnus W, Journal of physics : condensed matter 28, 365302 (2016). http://doi.org/10.1088/0953-8984/28/36/365302
Abstract: Fermi's golden rule underpins the investigation of mobile carriers propagating through various solids, being a standard tool to calculate their scattering rates. As such, it provides a perturbative estimate under the implicit assumption that the effect of the interaction Hamiltonian which causes the scattering events is sufficiently small. To check the validity of this assumption, we present a general framework to derive simple validity criteria in order to assess whether the scattering rates can be trusted for the system under consideration, given its statistical properties such as average size, electron density, impurity density et cetera. We derive concrete validity criteria for metallic nanowires with conduction electrons populating a single parabolic band subjected to different elastic scattering mechanisms: impurities, grain boundaries and surface roughness.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 2
DOI: 10.1088/0953-8984/28/36/365302
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“The 30-band k . p theory of valley splitting in silicon thin layers”. Cukaric NA, Partoens B, Tadic MZ, Arsoski VV, Peeters FM, Journal of physics : condensed matter 28, 195303 (2016). http://doi.org/10.1088/0953-8984/28/19/195303
Abstract: The valley splitting of the conduction-band states in a thin silicon-on-insulator layer is investigated using the 30-band k . p theory. The system composed of a few nm thick Si layer embedded within thick SiO2 layers is analyzed. The valley split states are found to cross periodically with increasing quantum well width, and therefore the energy splitting is an oscillatory function of the quantum well width, with period determined by the wave vector K-0 of the conduction band minimum. Because the valley split states are classified by parity, the optical transition between the ground hole state and one of those valley split conduction band states is forbidden. The oscillations in the valley splitting energy decrease with electric field and with smoothing of the composition profile between the well and the barrier by diffusion of oxygen from the SiO2 layers to the Si quantum well. Such a smoothing also leads to a decrease of the interband transition matrix elements. The obtained results are well parametrized by the effective two-valley model, but are found to disagree from previous 30-band calculations. This discrepancy could be traced back to the fact that the basis for the numerical solution of the eigenproblem must be restricted to the first Brillouin zone in order to obtain quantitatively correct results for the valley splitting.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
DOI: 10.1088/0953-8984/28/19/195303
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“Giant magnetic anisotropy in doped single layer molybdenum disulfide and fluorographene”. Sivek J, Sahin H, Partoens B, Peeters FM, Journal of physics : condensed matter 28, 195301 (2016). http://doi.org/10.1088/0953-8984/28/19/195301
Abstract: Stable monolayer materials based on existing, well known and stable two-dimensional crystal fluorographene and molybdenum disulfide are predicted to exhibit a huge magnetocrystalline anisotropy when functionalized with adsorbed transition metal atoms at vacant sides. Ab initio calculations within the density-functional theory formalism were performed to investigate the adsorption of the transitional metals in a single S (or F) vacancy of monolayer molybdenum disulfide (or fluorographene). We found strong bonding of the transitional metal atoms to the vacant sites with binding energies ranging from 2.5 to 5.2 eV. Our calculations revealed that these systems with adsorbed metal atoms exhibit a magnetic anisotropy, specifically the structures including Os and Ir show a giant magnetocrystalline anisotropy energy of 31-101 meV. Our results demonstrate the possibility of obtaining stable monolayer materials with huge magnetocrystalline anisotropy based on preexisting, well known and stable two-dimensional crystals: fluorographene and molybdenum disulfide. We believe that the results obtained here are useful not only for deeper understanding of the origin of magnetocrystalline anisotropy but also for the design of monolayer optoelectronic devices with novel functionalities.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 7
DOI: 10.1088/0953-8984/28/19/195301
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“Quantum-size effects and thermal response of anti-Kramer-Pesch vortex core”. Chen Y, Hong-Yu W, Peeters FM, Shanenko AA, Journal of physics : condensed matter 27, 125701 (2015). http://doi.org/10.1088/0953-8984/27/12/125701
Abstract: Since the 1960's it has been well known that the basic superconductive quantities can exhibit oscillations as functions of the thickness (diameter) in superconducting nanofilms (nanowires) due to the size quantization of the electronic spectrum. However, very little is known about the effects of quantum confinement on the microscopic properties of vortices. Based on a numerical solution to the Bogoliubov-de Gennes equations, we study the quantum-size oscillations of the vortex core resulting from the sequential interchange of the Kramer-Pesch and anti-Kramer-Pesch regimes with changing nanocylinder radius. The physics behind the anti-Kramer-Pesch anomaly is displayed by utilizing a semi-analytical Anderson approximate solution. We also demonstrate that the anti-Kramer-Pesch vortex core is robust against thermal smearing and results in a distinctive two-maxima structure in the local density of states, which can be used to identify the existence of the anti-Kramer-Pesch vortex.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 4
DOI: 10.1088/0953-8984/27/12/125701
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“Electronic and optical properties of core-shell nanowires in a magnetic field”. Ravi Kishore VV, Partoens B, Peeters FM, Journal of physics : condensed matter 26, 095501 (2014). http://doi.org/10.1088/0953-8984/26/9/095501
Abstract: The electronic and optical properties of zincblende nanowires are investigated in the presence of a uniform magnetic field directed along the [001] growth direction within the k . p method. We focus our numerical study on core-shell nanowires consisting of the III-V materials GaAs, AlxGa1-xAs and AlyGa1-y/0.51In0.49P. Nanowires with electrons confined in the core exhibit a Fock-Darwin-like spectrum, whereas nanowires with electrons confined in the shell show Aharonov-Bohm oscillations. Thus, by properly choosing the core and the shell materials of the nanowire, the optical properties in a magnetic field can be tuned in very different ways.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 10
DOI: 10.1088/0953-8984/26/9/095501
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“Surface correlation effects in two-band strongly correlated slabs”. Nasr Esfahani D, Covaci L, Peeters FM, Journal of physics : condensed matter 26, 075601 (2014). http://doi.org/10.1088/0953-8984/26/7/075601
Abstract: Using an extension of the Gutzwiller approximation for an inhomogeneous system, we study the two-band Hubbard model with unequal band widths for a slab geometry. The aim is to investigate the mutual effect of individual bands on the spatial distribution of quasi-particle weight and charge density, especially near the surface of the slab. The main effect of the difference in band width is the presence of two different length scales corresponding to the quasi-particle profile of each band. This is enhanced in the vicinity of the critical interaction of the narrow band where an orbitally selective Mott transition occurs and a surface dead layer forms for the narrow band. For the doped case, two different regimes of charge transfer between the surface and the bulk of the slab are revealed. The charge transfer from surface/ center to center/ surface depends on both the doping level and the average relative charge accumulated in each band. Such effects could also be of importance when describing the accumulation of charges at the interface between structures made of multi-band strongly correlated materials.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 1
DOI: 10.1088/0953-8984/26/7/075601
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“Angle-resolved synchrotron photoemission and density functional theory on the iridium modified Si(111) surface”. Oncel N, Çakir D, Dil JH, Slomski B, Landolt G, Journal of physics : condensed matter 26, 285501 (2014). http://doi.org/10.1088/0953-8984/26/28/285501
Abstract: The physical and electronic properties of the Ir modified Si(1 1 1) surface have been investigated with the help of angle resolved photoemission spectroscopy and density functional theory. The surface consists of Ir-ring clusters that form a root 7 x root 7 -R19.1 degrees reconstruction. A comparison between the measured and calculated band structure of the system reveals that the dispersions of the projected bulk states and the states originating from '1x1' domains are heavily modified due to Umklapp scattering from the surface Brillouin zone. Density of states calculations show that Ir-ring clusters contribute to the states in the vicinity of the Fermi level.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 4
DOI: 10.1088/0953-8984/26/28/285501
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“Conductance maps of quantum rings due to a local potential perturbation”. Petrovic MD, Peeters FM, Chaves A, Farias GA, Journal of physics : condensed matter 25, 495301 (2013). http://doi.org/10.1088/0953-8984/25/49/495301
Abstract: We performed a numerical simulation of the dynamics of a Gaussian shaped wavepacket inside a small sized quantum ring, smoothly connected to two leads and exposed to a perturbing potential of a biased atomic force microscope tip. Using the Landauer formalism, we calculated conductance maps of this system in the case of single and two subband transport. We explain the main features in the conductance maps as due to the AFM tip influence on the wavepacket phase and amplitude. In the presence of an external magnetic field, the tip modifies the phi(0) periodic Aharonov-Bohm oscillation pattern into a phi(0)/2 periodic Al'tshuler-Aronov-Spivak oscillation pattern. Our results in the case of multiband transport suggest tip selectivity to higher subbands, making them more observable in the total
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 12
DOI: 10.1088/0953-8984/25/49/495301
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“Perovskite transparent conducting oxides : an ab initio study”. Dabaghmanesh S, Saniz R, Amini MN, Lamoen D, Partoens B, Journal of physics : condensed matter 25, 415503 (2013). http://doi.org/10.1088/0953-8984/25/41/415503
Abstract: We present an ab initio study of the electronic structure and of the formation energies of various point defects in BaSnO3 and SrGeO3. We show that La and Y impurities substituting Ba or Sr are shallow donors with a preferred 1 + charge state. These defects have a low formation energy within all the suitable equilibrium growth conditions considered. Oxygen vacancies behave as shallow donors as well, preferring the 2 + charge state. Their formation energies, however, are higher in most growth conditions, indicating a limited contribution to conductivity. The calculated electron effective mass in BaSnO3, with a value of 0.21 me, and the very high mobility reported recently in La-doped BaSnO3 single-crystals, suggest that remarkably low scattering rates can be achieved in the latter. In the case of SrGeO3, our results point to carrier density and mobility values in the low range for typical polycrystalline TCOs, in line with experiment.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 2.649
Times cited: 17
DOI: 10.1088/0953-8984/25/41/415503
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“Quasiparticle band structure of rocksalt-CdO determined using maximally localized Wannier functions”. Dixit H, Lamoen D, Partoens B, Journal of physics : condensed matter 25, 035501 (2013). http://doi.org/10.1088/0953-8984/25/3/035501
Abstract: CdO in the rocksalt structure is an indirect band gap semiconductor. Thus, in order to determine its band gap one needs to calculate the complete band structure. However, in practice, the exact evaluation of the quasiparticle band structure for the large number of k-points which constitute the different symmetry lines in the Brillouin zone can be an extremely demanding task compared to the standard density functional theory (DFT) calculation. In this paper we report the full quasiparticle band structure of CdO using a plane-wave pseudopotential approach. In order to reduce the computational effort and time, we make use of maximally localized Wannier functions (MLWFs). The MLWFs offer a highly accurate method for interpolation of the DFT or GW band structure from a coarse k-point mesh in the irreducible Brillouin zone, resulting in a much reduced computational effort. The present paper discusses the technical details of the scheme along with the results obtained for the quasiparticle band gap and the electron effective mass.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 7
DOI: 10.1088/0953-8984/25/3/035501
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