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“Structural aspects and antiferromagnetic ordering in the “123&rdquo, derivative LnSr2Cu2Ga1-xFexO7-\delta (Ln = Y, Ho)”. Rykov A, Caignaert V, Van Tendeloo G, Greneche JM, Studer F, Nguyen N, Ducouret A, Bonville P, Raveau B, Journal of solid state chemistry 113, 94 (1994)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.133
Times cited: 9
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“Structural and vibrational properties of amorphous GeO2 from first-principles”. Scalise E, Houssa M, Pourtois G, Afanas'ev VV, Stesmans A, Applied physics letters 98, 202110 (2011). http://doi.org/10.1063/1.3593036
Abstract: The structural and vibrational properties of amorphous germanium oxide (a-GeO<sub>2</sub>) are investigated using first-principles calculations based on density functional theory. We first generate an a-GeO<sub>2</sub> structure by first-principles molecular dynamics and analyze its structural properties. The vibrational spectra is then calculated within a density-functional approach. Both static and dynamic properties are in good agreement with experimental data. We next generate defects in our structure (oxygen vacancies with several density and charge states) and consider the most stable atomic configurations, focusing on the vibrational features of threefold coordinated O and divalent Ge centers.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.411
Times cited: 226
DOI: 10.1063/1.3593036
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“Structural and physical properties of the new superconductor Hg0.5Pb0.5Sr4-xBaxCu2(CO3)O7-\delta”. Huvé, M, Van Tendeloo G, Hervieu M, Maignan A, Raveau B, Physica: C : superconductivity 231, 15 (1994). http://doi.org/10.1016/0921-4534(94)90138-4
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.942
Times cited: 14
DOI: 10.1016/0921-4534(94)90138-4
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“Structural and magnetotransport transitions in the electron-doped Pr1-xSrxMnO3(0.85\leq x\leq1) manganites”. Hervieu M, Martin C, Maignan A, Van Tendeloo G, Jirak Z, Hejtmanek J, Barnabe A, Thopart D, Raveau B, Chemistry and materials 12, 1456 (2000). http://doi.org/10.1021/cm000016o
Abstract: The exploration of the Mn4+-rich side of the Pr1-xSrxMnO3 system has allowed the extension of the domain of the cubic perovskite, by using a two-step process, combining synthesis under Ar flow at high temperature and O-2 pressure annealing at lower temperature. We show that these Pr-doped cubic perovskites exhibit a coupled structural (cubic-tetragonal) and magnetic (para-antiferro) transition connected with a resistivity jump at the same temperature. The strong interplay between lattice, charges, and spins for these oxides results from the appearance at low temperature of the distorted C-type antiferromagnetic structure. The Pr1-xSrxMnO3 magnetic phase diagram shows, for 0.9 less than or equal to x less than or equal to 1 (i.e., on the Mn4+-rich side), the existence at low temperature of C- and G-type antiferromagnetism. The absence of ferromagnetic-antiferromagnetic competition explains that magnetoresistante properties are not observed in this system, in contrast to Mn4+-rich Ln(1-x)Ca(x)MnO(3) systems.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 24
DOI: 10.1021/cm000016o
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“Structural and magnetic properties of the colossal magnetoresistance perovskite La0.85Ca0.15MnO3”. Lobanov MV, Balagurov AM, Pomjakushin VJ, Fischer P, Gutmann M, Abakumov AM, D'yachenko OG, Antipov EV, Lebedev OI, Van Tendeloo G, Physical review : B : condensed matter and materials physics 61, 8941 (2000). http://doi.org/10.1103/PhysRevB.61.8941
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 47
DOI: 10.1103/PhysRevB.61.8941
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“Structural and magnetic phase transitions in the AnBnO3n-2 anion-deficient perovskites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16”. Abakumov AM, Batuk M, Tsirlin AA, Tyablikov OA, Sheptyakov DV, Filimonov DS, Pokholok KV, Zhidal VS, Rozova MG, Antipov EV, Hadermann J, Van Tendeloo G;, Inorganic chemistry 52, 7834 (2013). http://doi.org/10.1021/ic3026667
Abstract: Novel anion-deficient perovskite-based ferrites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 were synthesized by solid-state reaction in air. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 belong to the perovskite-based AnBnO3n2 homologous series with n = 5 and 6, respectively, with a unit cell related to the perovskite subcell ap as ap√2 × ap × nap√2. Their structures are derived from the perovskite one by slicing it with 1/2[110]p(1̅01)p crystallographic shear (CS) planes. The CS operation results in (1̅01)p-shaped perovskite blocks with a thickness of (n 2) FeO6 octahedra connected to each other through double chains of edge-sharing FeO5 distorted tetragonal pyramids which can adopt two distinct mirror-related configurations. Ordering of chains with a different configuration provides an extra level of structure complexity. Above T ≈ 750 K for Pb2Ba2BiFe5O13 and T ≈ 400 K for Pb1.5Ba2.5Bi2Fe6O16 the chains have a disordered arrangement. On cooling, a second-order structural phase transition to the ordered state occurs in both compounds. Symmetry changes upon phase transition are analyzed using a combination of superspace crystallography and group theory approach. Correlations between the chain ordering pattern and octahedral tilting in the perovskite blocks are discussed. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 undergo a transition into an antiferromagnetically (AFM) ordered state, which is characterized by a G-type AFM ordering of the Fe magnetic moments within the perovskite blocks. The AFM perovskite blocks are stacked along the CS planes producing alternating FM and AFM-aligned FeFe pairs. In spite of the apparent frustration of the magnetic coupling between the perovskite blocks, all n = 4, 5, 6 AnFenO3n2 (A = Pb, Bi, Ba) feature robust antiferromagnetism with similar Néel temperatures of 623632 K.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.857
Times cited: 10
DOI: 10.1021/ic3026667
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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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“Structural and dynamical properties of a quasi-one-dimensional classical binary system”. Ferreira WP, Carvalho JCN, Oliveira PWS, Farias GA, Peeters FM, Physical review : B : condensed matter and materials physics 77, 014112 (2008). http://doi.org/10.1103/PhysRevB.77.014112
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 20
DOI: 10.1103/PhysRevB.77.014112
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“Structural and dynamical aspects of small three-dimensional spherical Coulomb clusters”. Apolinario SWS, Partoens B, Peeters FM, New journal of physics 9, 283 (2007). http://doi.org/10.1088/1367-2630/9/8/283
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.786
Times cited: 44
DOI: 10.1088/1367-2630/9/8/283
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“Structural analysis of CuInSe2, CuInTe2 and CuInSeTe by electron microscopy and X-ray techniques”. Leon M, Merino JM, Van Tendeloo G, Acta Microscopica 18, 128 (2009)
Abstract: A structural research of semiconductor compounds for photovoltaic applications CuInSe(2), CuInTe(2) and CuInSeTe, has been done by x-ray diffraction using the Rietveld analysis of experimental diagrams. Besides, in the CuInSeTe compound the electron diffraction and high resolution microscopy techniques have been used. All the studied compounds were polycrystals with chalcopyrite tetragonal structure, I. 42d. A model for the atomic occupancy in each compound has been proposed, and the results have been compared analyzing the Se-Te substitution effect.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.07
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“Strongly interacting σ-electrons and MgB2 superconductivity”. Ivanov VA, van den Broek M, Peeters FM, Solid state communications 120, 53 (2001). http://doi.org/10.1016/S0038-1098(01)00351-9
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.554
Times cited: 5
DOI: 10.1016/S0038-1098(01)00351-9
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Papp G, Peeters FM (2003) Strong wave-vector filtering and nearly 100% spin polarization through resonant tunneling antisymmetrical magnetic structure (vol 81, pg 691, 2002). American Institute of Physics, New York, N.Y., 3570–3570
Keywords: L1 Letter to the editor; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 21
DOI: 10.1063/1.1577821
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“Strong three-level resonant magnetopolaron effect due to the intersubband coupling in heavily modulation-doped GaAs/AlxGa1-xAs single quantum wells at high magnetic-fields”. Wang YJ, Leem YA, McCombe BD, Wu XG, Peeters FM, Jones ED, Reno JR, Lee XY, Jiang HW, Physical Review B 64, 161303 (2001). http://doi.org/10.1103/PhysRevB.64.161303
Abstract: Electron cyclotron resonance CR) measurements have been carried out in magnetic fields up to 32 T to study electron-phonon interaction in two heavily modulation-delta -doped GaAs/Al0.3Ga0.7As single-quantum-well samples. No measurable resonant magnetopolaron effects were observed in either sample in the region of the GaAs longitudinal optical (LO) phonons. However, when the CR frequency is above LO phonon frequency, omega (LO)=E-LO/(h) over bar, at high magnetic fields (B>27 T), electron CR exhibits a strong avoided-level-crossing splitting for both samples at frequencies close to (omega (LO)+ (E-2-E-1)1 (h) over bar, where E-2, and E-1 are the energies of the bottoms of the second and the first subbands, respectively. The energy separation between the two branches is large with the minimum separation of 40 cm(-1) occurring at around 30.5 T. A detailed theoretical analysis, which includes a self-consistent calculation of the band structure and the effects of electron-phonon interaction on the CR, shows that this type of splitting is due to a three-level resonance between the second Landau level of the first electron subband and the lowest Landau level of the second subband plus one GaAs LO phonon. The absence of occupation effects in the final states and weak screening or this three-level process yields large energy separation even in the presence of high electron densities. Excellent agreement between the theory and the experimental results is obtained.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 7
DOI: 10.1103/PhysRevB.64.161303
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“Strong resonant intersubband magnetopolaron effect in heavily modulation-doped GaAs/AlGaAs single quantum wells at high magnetic fields”. Wang YJ, Leem YA, McCombe BD, Wu XG, Peeters FM, Jones E, Reno J, Lee XY, Jiang HW, Physica. E: Low-dimensional systems and nanostructures 6, 195 (2000). http://doi.org/10.1016/S1386-9477(99)00086-7
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.221
Times cited: 2
DOI: 10.1016/S1386-9477(99)00086-7
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“Strong influence of nonlocal nonequilibrium effects on the dynamics of the order parameter in a phase-slip center: ring studies”. Vodolazov DY, Peeters FM, Physical review : B : condensed matter and materials physics 81, 184521 (2010). http://doi.org/10.1103/PhysRevB.81.184521
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.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 5
DOI: 10.1103/PhysRevB.81.184521
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“Strong enhancement of superconductivity in a nanosized Pb bridge”. Misko VR, Fomin VM, Devreese JT, Physical Review B 64, 014517 (2001). http://doi.org/10.1103/PhysRevB.64.014517
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 3.836
Times cited: 28
DOI: 10.1103/PhysRevB.64.014517
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“Strong-coupling limit for one-dimensional polarons in a finite box”. Vansant P, Smondyrev MA, Peeters FM, Devreese JT, Zeitschrift für Physik: B: condensed matter and quanta 99, 345 (1996). http://doi.org/10.1007/s002570050047
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Times cited: 1
DOI: 10.1007/s002570050047
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“Strong-coupling analysis of large bipolarons in two and three dimensions”. Verbist G, Smondyrev MA, Peeters FM, Devreese JT, Physical review : B : condensed matter and materials physics 45, 5262 (1992). http://doi.org/10.1103/PhysRevB.45.5262
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.736
Times cited: 68
DOI: 10.1103/PhysRevB.45.5262
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“Strong-coupling analysis of large bipolarons in 2 and 3 dimensions”. Verbist G, Smondyrev MA, Peeters FM, Devreese JT, Physical review : B : condensed matter and materials physics 45, 5262 (1992). http://doi.org/10.1103/PhysRevB.45.5262
Abstract: In the limit of strong electron-phonon coupling, we use either a Pekar-type or an oscillator wave function for the center-of-mass coordinate and either a Coulomb or an oscillator wave function for the relative coordinate, and are able to reproduce all the results from the literature for the large-bipolaron binding energy. Lower bounds are constructed for the critical ratio eta(c) of dielectric constants below which bipolarons can exist. It is found that, in the strong-coupling limit, the stability region for bipolaron formation is much larger in two dimensions (2D) than in 3D. We introduce a model that combines the averaging of the relative coordinate over the asymptotically best wave function with a path-integral treatment of the center-of-mass motion. The stability region for bipolaron formation is increased compared with the full path-integral treatment at large values of the coupling constant alpha. The critical values are alpha(c) almost-equal-to 9.3 in 3D and alpha(c) almost-equal-to 4.5 in 2D. Phase diagrams for the presented models are also obtained in both 2D and 3D.
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.736
Times cited: 68
DOI: 10.1103/PhysRevB.45.5262
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“Streaming-to-accumulation transition in a two-dimensional electron system in a polar semiconductor”. Wen X, Peeters FM, Devreese JT, Physical review : B : condensed matter and materials physics 46, 7571 (1992). http://doi.org/10.1103/PhysRevB.46.7571
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.736
Times cited: 13
DOI: 10.1103/PhysRevB.46.7571
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“Streaming-to-accumulation transition in a 2-dimensional electron-system in a polar semiconductor”. Xu W, Peeters FM, Devreese JT, Physical review : B : condensed matter and materials physics 46, 7571 (1992). http://doi.org/10.1103/PhysRevB.46.7571
Abstract: Hot-electron transport is studied for a two-dimensional electron gas coupled to longitudinal-optical phonons in crossed electric and magnetic fields. At low electric and high magnetic fields the electrons are accumulated, while at high electric fields they are in a streaming state. We develop a streaming-to-accumulation transition model and compare the results with that from a Monte Carlo simulation.
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.736
Times cited: 13
DOI: 10.1103/PhysRevB.46.7571
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“Strain relaxation and oxygen superstructure modulation in epitaxial Sr4Fe6O13\pm\delta films”. Santiso J, Pardo JA, Solis C, Garcia G, Figueras A, Rossell MD, Van Tendeloo G, Applied physics letters 86, 132105 (2005). http://doi.org/10.1063/1.1886264
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 5
DOI: 10.1063/1.1886264
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“Strain-induced semiconductor to metal transition in the two-dimensional honeycomb structure of MoS2”. Scalise E, Houssa M, Pourtois G, Afanas'ev V, Stesmans A, Nano Research 5, 43 (2012). http://doi.org/10.1007/s12274-011-0183-0
Abstract: The electronic properties of two-dimensional honeycomb structures of molybdenum disulfide (MoS(2)) subjected to biaxial strain have been investigated using first-principles calculations based on density functional theory. On applying compressive or tensile bi-axial strain on bi-layer and mono-layer MoS(2), the electronic properties are predicted to change from semiconducting to metallic. These changes present very interesting possibilities for engineering the electronic properties of two-dimensional structures of MoS(2).
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 7.354
Times cited: 407
DOI: 10.1007/s12274-011-0183-0
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“Strain-induced band gaps in bilayer graphene”. Verberck B, Partoens B, Peeters FM, Trauzettel B, Physical review : B : condensed matter and materials physics 85, 125403 (2012). http://doi.org/10.1103/PhysRevB.85.125403
Abstract: We present a tight-binding investigation of strained bilayer graphene within linear elasticity theory, focusing on the different environments experienced by the A and B carbon atoms of the different sublattices. We find that the inequivalence of the A and B atoms is enhanced by the application of perpendicular strain epsilon(zz), which provides a physical mechanism for opening a band gap, most effectively obtained when pulling the two graphene layers apart. In addition, perpendicular strain introduces electron-hole asymmetry and can result in linear electronic dispersion near the K point. Our findings suggest experimental means for strain-engineered band gaps in bilayer graphene.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 53
DOI: 10.1103/PhysRevB.85.125403
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“Strain-engineered graphene through a nanostructured substrate : 2 : pseudomagnetic fields”. Neek-Amal M, Peeters FM, Physical review : B : condensed matter and materials physics 85, 195446 (2012). http://doi.org/10.1103/PhysRevB.85.195446
Abstract: The strain-induced pseudomagnetic field in supported graphene deposited on top of a nanostructured substrate is investigated by using atomistic simulations. A step, an elongated trench, a one-dimensional barrier, a spherical bubble, a Gaussian bump, and a Gaussian depression are considered as support structures for graphene. From the obtained optimum configurations we found very strong induced pseudomagnetic fields which can reach up to similar to 1000 T due to the strain-induced deformations in the supported graphene. Different magnetic confinements with controllable geometries are found by tuning the pattern of the substrate. The resulting induced magnetic fields for graphene on top of a step, barrier, and trench are calculated. In contrast to the step and trench the middle part of graphene on top of a barrier has zero pseudomagnetic field. This study provides a theoretical background for designing magnetic structures in graphene by nanostructuring substrates. We found that altering the radial symmetry of the deformation changes the sixfold symmetry of the induced pseudomagnetic field.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 31
DOI: 10.1103/PhysRevB.85.195446
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“Strain-engineered graphene through a nanostructured substrate : 1 : deformations”. Neek-Amal M, Peeters FM, Physical review : B : condensed matter and materials physics 85, 195445 (2012). http://doi.org/10.1103/PhysRevB.85.195445
Abstract: Using atomistic simulations we investigate the morphological properties of graphene deposited on top of a nanostructured substrate. Sinusoidally corrugated surfaces, steps, elongated trenches, one-dimensional and cubic barriers, spherical bubbles, Gaussian bumps, and Gaussian depressions are considered as support structures for graphene. The graphene-substrate interaction is governed by van der Waals forces and the profile of the graphene layer is determined by minimizing the energy using molecular dynamics simulations. Based on the obtained optimum configurations, we found that (i) for graphene placed over sinusoidally corrugated substrates with corrugation wavelengths longer than 2 nm, the graphene sheet follows the substrate pattern while for supported graphene it is always suspended across the peaks of the substrate, (ii) the conformation of graphene to the substrate topography is enhanced when increasing the energy parameter in the van der Waals model, (iii) the adhesion of graphene into the trenches depends on the width of the trench and on the graphene's orientation, i. e., in contrast to a small-width (3 nm) nanoribbon with armchair edges, the one with zigzag edges follows the substrate profile, (iv) atomic-scale graphene follows a Gaussian bump substrate but not the substrate with a Gaussian depression, and (v) the adhesion energy due to van der Waals interaction varies in the range [0.1-0.4] J/m(2).
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 62
DOI: 10.1103/PhysRevB.85.195445
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“Strain and band-mixing effects on the excitonic Aharonov-Bohm effect in In(Ga)As/GaAs ringlike quantum dots”. Arsoski VV, Tadić, MZ, Peeters FM, Physical review : B : condensed matter and materials physics 87, 085314 (2013). http://doi.org/10.1103/PhysRevB.87.085314
Abstract: Neutral excitons in strained axially symmetric In(Ga)As/GaAs quantum dots with a ringlike shape are investigated. Similar to experimental self-assembled quantum rings, the analyzed quantum dots have volcano-like shapes. The continuum mechanical model is employed to determine the strain distribution, and the single-band envelope function approach is adopted to compute the electron states. The hole states are determined by the axially symmetric multiband Luttinger-Kohn Hamiltonian, and the exciton states are obtained from an exact diagonalization. We found that the presence of the inner layer covering the ring opening enhances the excitonic Aharonov-Bohm (AB) oscillations. The reason is that the hole becomes mainly localized in the inner part of the quantum dot due to strain, whereas the electron resides mainly inside the ring-shaped rim. Interestingly, larger AB oscillations are found in the analyzed quantum dot than in a fully opened quantum ring of the same width. Comparison with the unstrained ringlike quantum dot shows that the amplitude of the excitonic Aharonov-Bohm oscillations are almost doubled in the presence of strain. The computed oscillations of the exciton energy levels are comparable in magnitude to the oscillations measured in recent experiments. DOI: 10.1103/PhysRevB.87.085314
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 18
DOI: 10.1103/PhysRevB.87.085314
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“Strain and band edges in single and coupled cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots”. Tadić, M, Peeters FM, Janssens KL, Korkusinski M, Hawrylak P, Journal of applied physics 92, 5819 (2002). http://doi.org/10.1063/1.1510167
Abstract: A comparative study is made of the strain distribution in cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots as obtained from isotropic elasticity theory, the anisotropic continuum mechanical model, and from atomistic calculations. For the isotropic case, the recently proposed approach [J. H. Davies, J. Appl. Phys. 84, 1358 (1998)] is used, while the finite-element method, the valence force field method, and Stillinger-Weber potentials are employed to calculate the strain in anisotropic structures. We found that all four methods result in strain distributions of similar shapes, but with notable quantitative differences inside the dot and near the disk-matrix boundary. The variations of the diagonal strains with the height of the quantum dot, with fixed radius, as calculated from all models, are almost linear. Furthermore, the energies of the band edges in the two types of quantum dots are extracted from the multiband effective-mass theory by inserting the strain distributions as obtained by the four models. We demonstrated that all strain models produce effective potentials for the heavy and light holes which agree very well inside the dot. A negligible anisotropy of all normal strains in the (x,y) plane is found, which, providing the axial symmetry of the kinetic part of the multiband effective-mass Hamiltonian, justifies the use of the axial approximation. Strain propagation along the vertical direction is also considered with the aim to study the influence of strain on the electron coupling in stacks of quantum dots. We found that the interaction between the strain fields of the individual quantum dots makes the effective quantum wells for the electrons in the conduction band shallower, thereby counteracting the quantum mechanical coupling. (C) 2002 American Institute of Physics.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.068
Times cited: 73
DOI: 10.1063/1.1510167
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“Strain accommodation through facet matching in La1.85Sr0.15CuO4/Nd1.85Ce0.15CuO4 ramp-edge junctions”. Hoek M, Coneri F, Poccia N, Renshaw Wang X, Ke X, Van Tendeloo G, Hilgenkamp H, APL materials 3, 086101 (2015). http://doi.org/10.1063/1.4927796
Abstract: Scanning nano-focused X-ray diffraction and high-angle annular dark-field scanning transmission electron microscopy are used to investigate the crystal structure of ramp-edge junctions between superconducting electron-doped Nd1.85Ce0.15CuO4 and superconducting hole-doped La1.85Sr0.15CuO4 thin films, the latter being the top layer. On the ramp, a new growth mode of La1.85Sr0.15CuO4 with a 3.3° tilt of the c-axis is found. We explain the tilt by developing a strain accommodation model that relies on facet matching, dictated by the ramp angle, indicating that a coherent domain boundary is formed at the interface. The possible implications of this growth mode for the creation of artificial domains in morphotropic materials are discussed.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 4.335
Times cited: 4
DOI: 10.1063/1.4927796
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“Stone-Wales defects in silicene : formation, stability, and reactivity of defect sites”. Sahin H, Sivek J, Li S, Partoens B, Peeters FM, Physical review : B : condensed matter and materials physics 88, 045434 (2013). http://doi.org/10.1103/PhysRevB.88.045434
Abstract: During the synthesis of ultrathin materials with hexagonal lattice structure Stone-Wales (SW) type of defects are quite likely to be formed and the existence of such topological defects in the graphenelike structures results in dramatic changes of their electronic and mechanical properties. Here we investigate the formation and reactivity of such SW defects in silicene. We report the energy barrier for the formation of SW defects in freestanding (similar to 2.4 eV) and Ag(111)-supported (similar to 2.8 eV) silicene and found it to be significantly lower than in graphene (similar to 9.2 eV). Moreover, the buckled nature of silicene provides a large energy barrier for the healing of the SW defect and therefore defective silicene is stable even at high temperatures. Silicene with SW defects is semiconducting with a direct band gap of 0.02 eV and this value depends on the concentration of defects. Furthermore, nitrogen substitution in SW-defected silicene shows that the defect lattice sites are the least preferable substitution locations for the N atoms. Our findings show the easy formation of SW defects in silicene and also provide a guideline for band gap engineering in silicene-based materials through such defects.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 93
DOI: 10.1103/PhysRevB.88.045434
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