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“Critical currents of the phase slip process in the presence of electromagnetic radiation : rectification for time asymmetric ac signal”. Vodolazov DY, Elmuradov A, Peeters FM, Physical review : B : condensed matter and materials physics 72, 134509 (2005). http://doi.org/10.1103/PhysRevB.72.064509
Abstract: We studied theoretically the effect of time symmetric and asymmetric electromagnetic (e.m.) radiation on the phase-slip process in superconducting wires in the regime where there is no stimulation of superconductivity. We found that for large amplitudes j(ac) of the symmetric ac signal the value of the lower critical current j(c1)(j(ac)) at which the voltage vanishes in the sample oscillates as a function of j(ac). The amplitude of these oscillations decays with increasing power of the ac signal, and we explain it either by the existence of a maximal current j(c3) beyond which no phase slips can be created or by a weak heat removal from the sample. Applying an asymmetric in time signal (with zero dc current) we show that it may lead to a finite voltage in the system (i.e., ratchet effect). At high enough frequencies the rectified voltage is directly proportional to the frequency of the applied e.m. radiation. These properties resemble in many aspects the behavior of a Josephson junction under e.m. radiation. The differences are mainly connected to the effect of the transport current on the magnitude of the order parameter.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 35
DOI: 10.1103/PhysRevB.72.064509
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“Particle transport through an inductively coupled plasma torch: elemental droplet evaporation”. Aghaei M, Bogaerts A, Journal of analytical atomic spectrometry 31, 631 (2016). http://doi.org/10.1039/C5JA00162E
Abstract: We studied the transport of copper droplets through an inductively coupled plasma, connected to the sampling cone of a mass spectrometer, by means of a computational model. The sample droplets are followed until they become evaporated. They are inserted as liquid particles from the central inlet and the effects of injection position (i.e. “on” and “off” axis), droplet diameter, as well as mass loading flow rate are investigated. It is shown that more “on-axis” injection of the droplets leads to a more straight path line, so that the droplets move less in the radial direction and are evaporated more on the central axis, enabling a better sample transfer efficiency to the sampler cone. Furthermore, there are optimum ranges of diameters and flow rates, which guarantee the proper position of evaporation along the torch, i.e. not too early, so that the sample can get lost in the torch, and not too late, which reduces the chance of becoming ionized before reaching the sampler.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.379
Times cited: 21
DOI: 10.1039/C5JA00162E
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“Structure and spectrum of anisotropically confined two-dimensional clusters with logarithmic interaction”. Apolinario SWS, Partoens B, Peeters FM, Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics 72, 046122 (2005). http://doi.org/10.1103/PhysRevE.72.046122
Abstract: We studied the structural and spectral properties of a classical system consisting of a finite number of particles, moving in two dimensions, and interacting through a repulsive logarithmic potential and held together by an anisotropic harmonic potential. Increasing the anisotropy of the confinement potential can drive the system from a two-dimensional (2D) to a one-dimensional (1D) configuration. This change occurs through a sequence of structural transitions of first and second order which are reflected in the normal mode frequencies. Our results of the ground state configurations are compared with recent experiments and we obtained a satisfactory agreement. The transition from the 1D line structure to the 2D structure occurs through a zigzag transition which is of second order. We found analytical expressions for the eigenfrequencies before the zigzag transition, which allowed us to obtain an analytical expression for the anisotropy parameter at which the zigzag transition occurs as a function of the number of particles in the system.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.366
Times cited: 22
DOI: 10.1103/PhysRevE.72.046122
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“Phase formation and texture of thin nickel germanides on Ge(001) and Ge(111)”. De Schutter B, Van Stiphout K, Santos NM, Bladt E, Jordan-Sweet J, Bals S, Lavoie C, Comrie CM, Vantomme A, Detavernier C, Journal of applied physics 119, 135305 (2016). http://doi.org/10.1063/1.4945317
Abstract: We studied the solid-phase reaction between a thin Nifilm and a single crystal Ge(001) or Ge(111) substrate during a ramp anneal. The phase formation sequence was determined using in situX-ray diffraction and in situRutherford backscattering spectrometry (RBS), while the nature and the texture of the phases were studied using X-ray pole figures and transmission electron microscopy. The phase sequence is characterized by the formation of a single transient phase before NiGe forms as the final and stable phase. X-ray pole figures were used to unambiguously identify the transient phase as the ϵ-phase, a non-stoichiometric Ni-rich germanide with a hexagonal crystal structure that can exist for Ge concentrations between 34% and 48% and which forms with a different epitaxial texture on both substrate orientations. The complementary information gained from both RBS and X-ray pole figure measurements revealed a simultaneous growth of both the ϵ-phase and NiGe over a small temperature window on both substrate orientations.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.068
Times cited: 14
DOI: 10.1063/1.4945317
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“Plasma-catalytic ammonia synthesis : packed catalysts act as plasma modifiers”. Ndayirinde C, Gorbanev Y, Ciocarlan R-G, De Meyer R, Smets A, Vlasov E, Bals S, Cool P, Bogaerts A, Catalysis today 419, 114156 (2023). http://doi.org/10.1016/J.CATTOD.2023.114156
Abstract: We studied the plasma-catalytic production of NH3 from H2 and N2 in a dielectric barrier discharge plasma reactor using five different Co-based catalysts supported on Al2O3, namely Co/Al2O3, CoCe/Al2O3, CoLa/Al2O3, CoCeLa/Al2O3 and CoCeMg/Al2O3. The catalysts were characterized via several techniques, including SEM-EDX, and their performance was compared. The best performing catalyst was found to be CoLa/Al2O3, but the dif-ferences in NH3 concentration, energy consumption and production rate between the different catalysts were limited under the same conditions (i.e. feed gas, flow rate and ratio, and applied power). At the same time, the plasma properties, such as the plasma power and current profile, varied significantly depending on the catalyst. Taken together, these findings suggest that in the production of NH3 by plasma catalysis, our catalysts act as plasma modifiers, i.e., they change the discharge properties and hence the gas phase plasma chemistry. Importantly, this effect dominates over the direct catalytic effect (as e.g. in thermal catalysis) defined by the chemistry on the catalyst surface.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 5.3
Times cited: 3
DOI: 10.1016/J.CATTOD.2023.114156
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“Tunable exciton Aharonov-Bohm effect in a quantum ring”. Li B, Magnus W, Peeters FM, Journal of physics : conference series
T2 –, Proceedings of the 11th International Conference on Optics of Excitons in Confined Systems, September 7-11, 2009, Spain / Vina, L. [edit.], et al. [edit.] 210, 012030 (2010). http://doi.org/10.1088/1742-6596/210/1/012030
Abstract: We studied the optical Aharonov-Bohm effect for an exciton in a semiconductor quantum ring. A perpendicular electric field applied to a quantum ring with large height, is able to tune the exciton ground state energy such that it exhibits a weak observable Aharonov-Bohm oscillations. This Aharonov-Bohm effect is tunable in strength and period.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Times cited: 3
DOI: 10.1088/1742-6596/210/1/012030
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“Characterisation of multilayer ramp-type REBa2Cu3O7-\delta structures by scanning probe microscopy and high-resolution electron microscopy”. Blank DHA, Rijnders AJHM, Verhoeven MAJ, Bergs RMH, Rogalla H, Verbist K, Lebedev O, Van Tendeloo G, Journal of alloys and compounds
T2 –, Symposium on High Temperature Superconductor Thin Films, Growth, Mechanisms, Interfaces, Multilayers, at the 1996 Spring Meeting of the European-Materials-Society, June 04-07, 1996, Strasbourg, France 251, 206 (1997). http://doi.org/10.1016/S0925-8388(96)02799-5
Abstract: We studied the morphology of ramps in REBa2CU3O7 (REBCO) epitaxial films on SrTiO3 substrates, fabricated by RF magnetron sputter deposition and pulsed laser deposition (PLD), by scanning probe microscopy (SPM) and high resolution electron microscopy (HREM). The ramps were fabricated by Ar ion beam etching using masks of standard photoresist and TIN. AFM-studies on ramps in sputter deposited films show a strong dependence, i.e. formation of facets and ridges, on the angle of incidence of the ion beam with respect to the substrate surface as well as the rotation angle with respect to the crystal axes of the substrate. Ramps in pulsed laser deposited films did not show this dependence, Furthermore, we studied the effect of an anneal step prior to the deposition of barrier layers (i.e. PrBa2CU3O7, SrTiO3, CeO2) on the ramp. First results show a recrystallization of the ramp surface, resulting in terraces and a non-homogeneous growth of the barrier material on top of it. The thickness variations, for thin layers of barrier material, con even become much larger than expected from the amount of deposited material and are dependent on the deposition and anneal conditions. HREM studies show a well defined interface between barrier layer and electrodes. The angle of the ramp depends on the etch rate of the mask and REBCO, and on the angle of incidence of the ion beam. TiN has a much lower etch rate compared to photoresist, resulting in an angle of the ramp comparable to the angle of incidence, resulting in a low etching rate on the ramp. These results will lead to improved electrical characteristics of ramp-type junctions.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.133
DOI: 10.1016/S0925-8388(96)02799-5
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“Altering conversion and product selectivity of dry reforming of methane in a dielectric barrier discharge by changing the dielectric packing material”. Michielsen I, Uytdenhouwen Y, Bogaerts A, Meynen V, Catalysts 9, 51 (2019). http://doi.org/10.3390/CATAL9010051
Abstract: We studied the influence of dense, spherical packing materials, with different chemical compositions, on the dry reforming of methane (DRM) in a dielectric barrier discharge (DBD) reactor. Although not catalytically activated, a vast effect on the conversion and product selectivity could already be observed, an influence which is often neglected when catalytically activated plasma packing materials are being studied. The alpha-Al2O3 packing material of 2.0-2.24 mm size yields the highest total conversion (28%), as well as CO2 (23%) and CH4 (33%) conversion and a high product fraction towards CO (similar to 70%) and ethane (similar to 14%), together with an enhanced CO/H-2 ratio of 9 in a 4.5 mm gap DBD at 60 W and 23 kHz. gamma-Al2O3 is only slightly less active in total conversion (22%) but is even more selective in products formed than alpha-Al2O3 BaTiO3 produces substantially more oxygenated products than the other packing materials but is the least selective in product fractions and has a clear negative impact on CO2 conversion upon addition of CH4. Interestingly, when comparing to pure CO2 splitting and when evaluating differences in products formed, significantly different trends are obtained for the packing materials, indicating a complex impact of the presence of CH4 and the specific nature of the packing materials on the DRM process.
Keywords: A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.082
Times cited: 4
DOI: 10.3390/CATAL9010051
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“A XANES study of chromophores : the case of black glass”. Ceglia A, Nuyts G, Cagno S, Meulebroeck W, Baert K, Cosyns P, Nys K, Thienpont H, Janssens K, Terryn H, Analytical methods 6, 2662 (2014). http://doi.org/10.1039/C3AY42029A
Abstract: We studied the Fe K-edge X-ray absorption near edge (XANES) spectra of several Roman black glass fragments in order to determine the Fe3+/ΣFe ratio of these materials. The selected archaeological glass samples cover the period 1st5th century AD in nine different sites of the North Western provinces of the Roman Empire. The fragments belong to two different compositional groups demonstrating a diachronic evolution: early Roman HMG (High Magnesia Glass) and Roman Imperial LMG (Low Magnesia Glass). The first group contains natural Fe levels (below 2 wt% as Fe2O3), while the LMG has concentrations above 5 wt%. This difference is also reflected by Fe3+/ΣFe values. Low iron glass was produced under strongly reducing conditions in order to obtain the black colour, with average Fe3+/ΣFe values ≈ 0.17. LMG glass is somewhat more oxidised (Fe3+/ΣFe ≈ 0.40.5). While HMG glass required active control of the furnace environment, LMG was made under ambient atmosphere and its higher oxidation degree is mainly determined by the chemistry of the raw glass.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 1.9
Times cited: 14
DOI: 10.1039/C3AY42029A
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“Thermal instability and volume contraction in a pulsed microwave N2plasma at sub-atmospheric pressure”. Kelly S, van de Steeg A, Hughes A, van Rooij G, Bogaerts A, Plasma Sources Science &, Technology 30, 055005 (2021). http://doi.org/10.1088/1361-6595/abf1d6
Abstract: We studied the evolution of an isolated pulsed plasma in a vortex flow stabilised microwave (MW) discharge in N2 at 25 mbar via the combination of 0D kinetics modelling, iCCD imaging and laser scattering diagnostics. Quenching of electronically excited N2 results in fast gas heating and the onset of a thermal-ionisation instability, contracting the discharge volume. The onset of a thermal-ionisation instability driven by vibrational excitation pathways is found to facilitate significantly higher N2 conversion (i.e. dissociation to atomic N2 ) compared to pre-instability conditions, emphasizing the potential utility of this dynamic in future fixation applications. The instability onset is found to be instigated by super-elastic heating of the electron energy distribution tail via vibrationally excited N2 . Radial contraction of the discharge to the skin depth is found to occur post instability, while the axial elongation is found to be temporarily contracted during the thermal instability onset. An increase in power reflection during the thermal instability onset eventually limits the destabilising effects of exothermic electronically excited N2 quenching. Translational and vibrational temperature reach a quasi-non-equilibrium after the discharge contraction, with translational temperatures reaching ∼1200 K at the pulse end, while vibrational temperatures are found in near equilibrium with the electron energy (1 eV, or ∼11 600 K). This first description of the importance of electronically excited N2 quenching in thermal instabilities gives an additional fundamental understanding of N2 plasma behaviour in pulsed MW context, and thereby brings the eventual implementation of this novel N2 fixation method one step closer.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.302
DOI: 10.1088/1361-6595/abf1d6
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“Effect of sample geometry on the phase boundary of a mesoscopic superconducting loop”. Berdiyorov GR, Yu SH, Xiao ZL, Peeters FM, Hua J, Imre A, Kwok WK, Physical review : B : solid state 80, 064511 (2009). http://doi.org/10.1103/PhysRevB.80.064511
Abstract: We studied the effect of sample geometry on the evolution of the superconducting state in nanoscale Nb circular and square loops by transport measurements. A multistage resistive transition with temperature is found for both samples, which is related to the effect of contact leads made from the same superconducting material. The H-T phase diagrams close to Tc0 show clear periodic oscillations on top of a parabolic background, i.e., Little-Parks effect. However, the amplitude of the oscillations decreases faster in the circular loop compared to the one in the square sample. Numerical simulations are conducted within the nonlinear Ginzburg-Landau theory to show the effect of sample geometry on the nucleation of superconductivity in superconducting loop structures.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 21
DOI: 10.1103/PhysRevB.80.064511
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“Dielectric mismatch effect on coupled impurity states in a freestanding nanowire”. Li B, Partoens B, Peeters FM, Magnus W, Microelectronics journal 40, 446 (2009). http://doi.org/10.1016/j.mejo.2008.06.028
Abstract: We studied the coupled impurity states in a freestanding semiconductor nanowire (NW), within the effective mass approximation and including the effect of the dielectric mismatch, by using finite element method. Bonding and anti-bonding states are found and their energies converge with increasing distance di between the two impurities. The dependence of the binding energy on the wire radius R and the distance di between the two impurities is investigated, and we compare it with the result of a freestanding NW that contains a single impurity.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.163
Times cited: 4
DOI: 10.1016/j.mejo.2008.06.028
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“H2S Decomposition into H2 and S2 by Plasma Technology: Comparison of Gliding Arc and Microwave Plasma”. Zhang Q-Z, Wang WZ, Thille C, Bogaerts A, Plasma Chemistry And Plasma Processing 40, 1163 (2020). http://doi.org/10.1007/s11090-020-10100-3
Abstract: We studied hydrogen sulfide (H2S) decomposition into hydrogen (H2) and sulfur (S2) in a gliding arc plasmatron (GAP) and microwave (MW) plasma by a combination of 0D and 2D models. The conversion, energy efficiency, and plasma distribution are examined for different discharge conditions, and validated with available experiments from literature. Furthermore, a comparison is made between GAP and MW plasma. The GAP operates at atmospheric pressure, while the MW plasma experiments to which comparison is made were performed at reduced pressure. Indeed, the MW discharge region becomes very much contracted near atmospheric pressure, at the conditions under study, as revealed by our 2D model. The models predict that thermal reactions play the most important role in H2S decomposition in both plasma types. The GAP has a higher energy efficiency but lower conversion than the MW plasma at their typical conditions. When compared at the same conversion, the GAP exhibits a higher energy efficiency and lower energy cost than the MW plasma.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.6
DOI: 10.1007/s11090-020-10100-3
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“Normal modes of a quasi-one-dimensional multichain complex plasma”. Piacente G, Peeters FM, Betouras JJ, Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics 70 (2004). http://doi.org/10.1103/PhysRevE.70.036406
Abstract: We studied equally charged particles, suspended in a complex plasma, which move in a plane and interact with a screened Coulomb potential (Yukawa type) and with an additional external confining parabolic potential in one direction, which makes the system quasi-one-dimensional (Q1D). The normal modes of the system are studied in the presence of dissipation. We also investigated how a perpendicular magnetic field couples the phonon modes with each other. Two different ways of exciting the normal modes are discussed: (1) a uniform excitation of the Q1D lattice, and (2) a local forced excitation of the system in which one particle is driven by, e.g., a laser. Our results are in very good agreement with recent experimental findings on a finite single chain system [Liu , Phys. Rev. Lett. 91, 255003 (2003)]. Predictions are made for the normal modes of multichain structures in the presence of damping.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.366
Times cited: 18
DOI: 10.1103/PhysRevE.70.036406
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“Response to mixed substrate feeds of the structure and activity of a linuron-degrading triple-species biofilm”. Bruegelmans P, Horemans B, Hofkens J, Springael D, Research in microbiology 161, 660 (2010). http://doi.org/10.1016/J.RESMIC.2010.06.006
Abstract: We sought to determine whether the pesticide-degrading performance of a multi-species bacterial biofilm is affected by co-occurrence of multiple nutrient sources Thus, the 3-(3,4-dichlorophenyl)-l-methoxy-l-methyl urea (linuron)-degrading activity of a triple-species linuron-degrading consortium, cultivated in continuous flow biofilm systems, was monitored when exposed to mixed substrate feeds which contained, in addition to linuron, readily assimilated carbon (i e citrate and trypticase soy broth) and/or nitrogen (i e ammonium) sources The addition of alternative carbon sources at different concentrations resulted in diminished linuron degradation efficiency In addition, the efficiency of removal of the linuron metabolite 3,4-dichloroaniline was affected These effects might be attributed to catabolic repression of the linuron metabolic pathway in the presence of alternative carbon substrates Moreover, each nutrient condition resulted in a particular biofilm composition and a particular spatial and structural organization, which might also be related to the performance of the biofilm community Results show that the activity of pesticide-degrading biofilms strongly depends on prevailing nutrient conditions and that the ideal biofilm configuration and activity, as observed under selective conditions, does not exist in real-life environmental conditions where mixtures of substrates are often present (C) 2010 Elsevier Masson SAS All rights reserved.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.RESMIC.2010.06.006
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“Analytic treatment of vortex states in cylindrical superconductors in applied axial magnetic field”. Ludu A, Van Deun J, Milošević, MV, Cuyt A, Peeters FM, Journal of mathematical physics 51, 082903 (2010). http://doi.org/10.1063/1.3470767
Abstract: We solve the linear GinzburgLandau (GL) equation in the presence of a uniform magnetic field with cylindrical symmetry and we find analytic expressions for the eigenfunctions in terms of the confluent hypergeometric functions. The discrete spectrum results from an implicit equation associated to the boundary conditions and it is resolved in analytic form using the continued fractions formalism. We study the dependence of the spectrum and the eigenfunctions on the sample size and the surface conditions for solid and hollow cylindrical superconductors. Finally, the solutions of the nonlinear GL formalism are constructed as expansions in the linear GL eigenfunction basis and selected by minimization of the free energy. We present examples of vortex states and their energies for different samples in enhancing/suppressing superconductivity surroundings.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.077
Times cited: 10
DOI: 10.1063/1.3470767
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“Vortex states in axially symmetric superconductors in applied magnetic field”. Ludu A, Milošević, MV, Peeters FM, Sn –, 0378-4754 82, 1258 (2012). http://doi.org/10.1016/j.matcom.2012.02.001
Abstract: We solve analytically the linearized Ginzburg-Landau (GL) equation in the presence of an uniform magnetic field with cylindrical boundary conditions. The solution of the non-linear GL equation is provided as an expansion in the basis of linearized solutions. We present examples of the resulting vortex structure for a solid and perforated superconducting cylinder. (C) 2012 IMACS. Published by Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.218
Times cited: 1
DOI: 10.1016/j.matcom.2012.02.001
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“Two-band superconductors : hidden criticality deep in the superconducting state”. Komendová, L, Chen Y, Shanenko AA, Milošević, MV, Peeters FM, Physical review letters 108, 207002 (2012). http://doi.org/10.1103/PhysRevLett.108.207002
Abstract: We show that two-band superconductors harbor hidden criticality deep in the superconducting state, stemming from the critical temperature of the weaker band taken as an independent system. For sufficiently small interband coupling gamma the coherence length of the weaker band exhibits a remarkable deviation from the conventional monotonic increase with temperature, namely, a pronounced peak close to the hidden critical point. The magnitude of the peak scales as proportional to gamma(-mu), with the Landau critical exponent mu = 1/3, the same as found for the mean-field critical behavior with respect to the source field in ferromagnets and ferroelectrics. Here reported hidden criticality of multiband superconductors can be experimentally observed by, e.g., imaging of the variations of the vortex core in a broader temperature range. Similar effects are expected for the superconducting multilayers.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 8.462
Times cited: 75
DOI: 10.1103/PhysRevLett.108.207002
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“Kronig-Penney model on bilayer graphene : spectrum and transmission periodic in the strength of the barriers”. Barbier M, Vasilopoulos P, Peeters FM, Physical review : B : condensed matter and materials physics 82, 235408 (2010). http://doi.org/10.1103/PhysRevB.82.235408
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.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 34
DOI: 10.1103/PhysRevB.82.235408
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“Wavevector filtering through single-layer and bilayer graphene with magnetic barrier structures”. Masir MR, Vasilopoulos P, Peeters FM, Applied physics letters 93, 242103 (2008). http://doi.org/10.1063/1.3049600
Abstract: We show that the angular range of the transmission through magnetic barrier structures can be efficiently controlled in single-layer and bilayer graphenes and this renders the structures efficient wavevector filters. As the number of magnetic barriers increases, this range shrinks, the gaps in the transmission versus energy become wider, and the conductance oscillates with the Fermi energy.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 91
DOI: 10.1063/1.3049600
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“Spin-reorientation transitions in the Cairo pentagonal magnet Bi4Fe5O13F”. Tsirlin AA, Rousochatzakis I, Filimonov D, Batuk D, Frontzek M, Abakumov AM, Physical review B 96, 094420 (2017). http://doi.org/10.1103/PhysRevB.96.094420
Abstract: We show that interlayer spins play a dual role in the Cairo pentagonal magnet Bi4Fe5O13F, on one hand mediating the three-dimensional magnetic order, and on the other driving spin-reorientation transitions both within and between the planes. The corresponding sequence of magnetic orders unraveled by neutron diffraction and Mossbauer spectroscopy features two orthogonal magnetic structures described by opposite local vector chiralities, and an intermediate, partly disordered phase with nearly collinear spins. A similar collinear phase has been predicted theoretically to be stabilized by quantum fluctuations, but Bi4Fe5O13F is very far from the relevant parameter regime. While the observed in-plane reorientation cannot be explained by any standard frustration mechanism, our ab initio band-structure calculations reveal strong single-ion anisotropy of the interlayer Fe3+ spins that turns out to be instrumental in controlling the local vector chirality and the associated interlayer order.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 7
DOI: 10.1103/PhysRevB.96.094420
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“The ground states of the two-component order parameter superconductor”. Doria MM, de Romaguera ARC, Peeters FM, Europhysics letters 92, 17004 (2010). http://doi.org/10.1209/0295-5075/92/17004
Abstract: We show that in presence of an applied external field the two-component order parameter superconductor falls in two categories of ground states, namely, in the traditional Abrikosov ground state or in a new ground state fitted to describe a superconducting layer with texture, that is, patched regions separated by a phase difference of pi. The existence of these two kinds of ground states follows from the sole assumption that the total supercurrent is the sum of the two individual supercurrents and is independent of any consideration about the free energy expansion. Uniquely defined relations between the current density and the superfluid density hold for these two ground states, which also determine the magnetization in terms of average values of the order parameters. Because these ground-state conditions are also Bogomolny equations we construct the free energy for the two-component superconductor which admits the Bogomolny solution at a special coupling value. Copyright (C) EPLA, 2010
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.957
Times cited: 8
DOI: 10.1209/0295-5075/92/17004
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“Can p-channel tunnel field-effect transistors perform as good as n-channel?”.Verhulst AS, Verreck D, Pourghaderi MA, Van de Put M, Sorée B, Groeseneken G, Collaert N, Thean AV-Y, Applied physics letters 105, 043103 (2014). http://doi.org/10.1063/1.4891348
Abstract: We show that bulk semiconductor materials do not allow perfectly complementary p- and n-channel tunnel field-effect transistors (TFETs), due to the presence of a heavy-hole band. When tunneling in p-TFETs is oriented towards the gate-dielectric, field-induced quantum confinement results in a highest-energy subband which is heavy-hole like. In direct-bandgap IIIV materials, the most promising TFET materials, phonon-assisted tunneling to this subband degrades the subthreshold swing and leads to at least 10x smaller on-current than the desired ballistic on-current. This is demonstrated with quantum-mechanical predictions for p-TFETs with tunneling orthogonal to the gate, made out of InP, In0.53Ga0.47As, InAs, and a modified version of In0.53Ga0.47As with an artificially increased conduction-band density-of-states. We further show that even if the phonon-assisted current would be negligible, the build-up of a heavy-hole-based inversion layer prevents efficient ballistic tunneling, especially at low supply voltages. For p-TFET, a strongly confined n-i-p or n-p-i-p configuration is therefore recommended, as well as a tensily strained line-tunneling configuration. (C) 2014 AIP Publishing LLC.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 8
DOI: 10.1063/1.4891348
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“Electron collimation at van der Waals domain walls in bilayer graphene”. Abdullah HM, da Costa DR, Bahlouli H, Chaves A, Peeters FM, Van Duppen B, Physical review B 100, 045137 (2019). http://doi.org/10.1103/PHYSREVB.100.045137
Abstract: We show that a domain wall separating single-layer graphene and AA-stacked bilayer graphene (AA-BLG) can be used to generate highly collimated electron beams which can be steered by a magnetic field. Two distinct configurations are studied, namely, locally delaminated AA-BLG and terminated AA-BLG whose terminal edge types are assumed to be either zigzag or armchair. We investigate the electron scattering using semiclassical dynamics and verify the results independently with wave-packet dynamics simulations. We find that the proposed system supports two distinct types of collimated beams that correspond to the lower and upper cones in AA-BLG. Our computational results also reveal that collimation is robust against the number of layers connected to AA-BLG and terminal edges.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 12
DOI: 10.1103/PHYSREVB.100.045137
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“Unconventional two-dimensional vibrations of a decorated carbon nanotube under electric field : linking actuation to advanced sensing ability”. de Aquino BRH, Neek-Amal M, Milošević, MV, Scientific reports 7, 13481 (2017). http://doi.org/10.1038/S41598-017-12647-2
Abstract: We show that a carbon nanotube decorated with different types of charged metallic nanoparticles exhibits unusual two-dimensional vibrations when actuated by applied electric field. Such vibrations and diverse possible trajectories are not only fundamentally important but also have minimum two characteristic frequencies that can be directly linked back to the properties of the constituents in the considered nanoresonator. Namely, those frequencies and the maximal deflection during vibrations are very distinctively dependent on the geometry of the nanotube, the shape, element, mass and charge of the nanoparticle, and are vastly tunable by the applied electric field, revealing the unique sensing ability of devices made of molecular filaments and metallic nanoparticles.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 4.259
Times cited: 1
DOI: 10.1038/S41598-017-12647-2
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“Ground-state multiquantum vortices in rotating two-species superfluids”. Kuopanportti P, Orlova NV, Milošević, MV, Physical review : A : atomic, molecular and optical physics 91, 043605 (2015). http://doi.org/10.1103/PhysRevA.91.043605
Abstract: We show numerically that a rotating, harmonically trapped mixture of two Bose-Einstein-condensed superfluids cancontrary to its single-species counterpartcontain a multiply quantized vortex in the ground state of the system. This giant vortex can occur without any accompanying single-quantum vortices, may either be coreless or have an empty core, and can be realized in a Rb87−K41 Bose-Einstein condensate. Our results not only provide a rare example of a stable, solitary multiquantum vortex but also reveal exotic physics stemming from the coexistence of multiple, compositionally distinct condensates in one system.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.925
Times cited: 25
DOI: 10.1103/PhysRevA.91.043605
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“Skyrmionic vortex lattices in coherently coupled three-component Bose-Einstein condensates”. Orlova NV, Kuopanportti P, Milošević, MV, Physical Review A 94, 023617 (2016). http://doi.org/10.1103/PHYSREVA.94.023617
Abstract: We show numerically that a harmonically trapped and coherently Rabi-coupled three-component Bose-Einstein condensate can host unconventional vortex lattices in its rotating ground state. The discovered lattices incorporate square and zig-zag patterns, vortex dimers and chains, and doubly quantized vortices, and they can be quantitatively classified in terms of a skyrmionic topological index, which takes into account the multicomponent nature of the system. The exotic ground-state lattices arise due to the intricate interplay of the repulsive density-density interactions and the Rabi couplings as well as the ubiquitous phase frustration between the components. In the frustrated state, domain walls in the relative phases can persist between some components even at strong Rabi coupling, while vanishing between others. Consequently, in this limit the three-component condensate effectively approaches a two-component condensate with only density-density interactions. At intermediate Rabi coupling strengths, however, we face unique vortex physics that occurs neither in the two-component counterpart nor in the purely density-density-coupled three-component system.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.925
Times cited: 16
DOI: 10.1103/PHYSREVA.94.023617
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“Large magnetoresistance oscillations in mesoscopic superconductors due to current-excited moving vortices”. Berdiyorov GR, Milošević, MV, Latimer ML, Xiao ZL, Kwok WK, Peeters FM, Physical review letters 109, 057004 (2012). http://doi.org/10.1103/PhysRevLett.109.057004
Abstract: We show in the case of a superconducting Nb ladder that a mesoscopic superconductor typically exhibits magnetoresistance oscillations whose amplitude and temperature dependence are different from those stemming from the Little-Parks effect. We demonstrate that these large resistance oscillations (as well as the monotonic background on which they are superimposed) are due to current-excited moving vortices, where the applied current in competition with the oscillating Meissner currents imposes or removes the barriers for vortex motion in an increasing magnetic field. Because of the ever present current in transport measurements, this effect should be considered in parallel with the Little-Parks effect in low-critical temperature (T-c) samples, as well as with recently proposed thermal activation of dissipative vortex-antivortex pairs in high-T-c samples.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 8.462
Times cited: 65
DOI: 10.1103/PhysRevLett.109.057004
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“Confined magnetic guiding orbit states”. Reijniers J, Matulis A, Chang K, Peeters FM, Vasilopoulos P, Europhysics letters 59, 749 (2002). http://doi.org/10.1209/epl/i2002-00189-8
Abstract: We show how snake-orbit states which run along a magnetic edge can be confined electrically. We consider a two-dimensional electron gas (2DEG) confined into a quantum wire, subjected to a strong perpendicular and steplike magnetic field B/ − B. Close to this magnetic step, new, spatially confined bound states arise as a result of the lateral confinement and the magnetic-field step. The number of states, with energy below the first Landau level, increases as B becomes stronger or as the wire width becomes larger. These bound states can be understood as an interference between two counter-propagating one-dimensional snake-orbit states.
Keywords: A1 Journal article; Engineering Management (ENM); Condensed Matter Theory (CMT)
Impact Factor: 1.957
Times cited: 26
DOI: 10.1209/epl/i2002-00189-8
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“Vortex manipulation in a superconducting matrix with view on applications”. Milošević, MV, Peeters FM, Applied physics letters 96, 192501 (2010). http://doi.org/10.1063/1.3425672
Abstract: We show how a single flux quantum can be effectively manipulated in a superconducting film with a matrix of blind holes. Such a sample can serve as a basic memory element, where the position of the vortex in a k×l matrix of pinning sites defines the desired combination of n bits of information (2n = k×l). Vortex placement is achieved by strategically applied current and the resulting position is read out via generated voltage between metallic contacts on the sample. Such a device can also act as a controllable source of a nanoengineered local magnetic field for, e.g., spintronics applications.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 14
DOI: 10.1063/1.3425672
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