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“Peierls distortion, magnetism, and high hardness of manganese tetraboride”. Gou H, Tsirlin AA, Bykova E, Abakumov AM, Van Tendeloo G, Richter A, Ovsyannikov SV, Kurnosov AV, Trots DM, Konôpková, Z, Liermann HP, Dubrovinsky L, Dubrovinskaia N;, Physical review : B : condensed matter and materials physics 89, 064108 (2014). http://doi.org/10.1103/PhysRevB.89.064108
Abstract: We report crystal structure, electronic structure, and magnetism of manganese tetraboride, MnB4, synthesized under high-pressure, high-temperature conditions. In contrast to superconducting FeB4 and metallic CrB4, which are both orthorhombic, MnB4 features a monoclinic crystal structure. Its lower symmetry originates from a Peierls distortion of the Mn chains. This distortion nearly opens the gap at the Fermi level, but despite the strong dimerization and the proximity of MnB4 to the insulating state, we find indications for a sizable paramagnetic effective moment of about 1.7 mu(B)/f.u., ferromagnetic spin correlations, and, even more surprisingly, a prominent electronic contribution to the specific heat. However, no magnetic order has been observed in standard thermodynamic measurements down to 2 K. Altogether, this renders MnB4 a structurally simple but microscopically enigmatic material; we argue that its properties may be influenced by electronic correlations.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 39
DOI: 10.1103/PhysRevB.89.064108
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“Phase diagram for large two dimensional bipolarons in a magnetic field”. da Costa WB, Peeters FM, Physical review : B : condensed matter and materials physics 57, 10569 (1998). http://doi.org/10.1103/PhysRevB.57.10569
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 8
DOI: 10.1103/PhysRevB.57.10569
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“Phase separation and frustrated square lattice magnetism of Na1.5VOPO4F0.5”. Tsirlin AA, Nath R, Abakumov AM, Furukawa Y, Johnston DC, Hemmida M, Krug von Nidda H-A, Loidl A, Geibel C, Rosner H, Physical review : B : condensed matter and materials physics 84, 014429 (2011). http://doi.org/10.1103/PhysRevB.84.014429
Abstract: Crystal structure, electronic structure, and magnetic behavior of the spin-1/2 quantum magnet Na1.5VOPO4F0.5 are reported. The disorder of Na atoms leads to a sequence of structural phase transitions revealed by synchrotron x-ray powder diffraction and electron diffraction. The high-temperature second-order α↔β transition at 500 K is of the order-disorder type, whereas the low-temperature β↔γ+γ′ transition around 250 K is of the first order and leads to a phase separation toward the polymorphs with long-range (γ) and short-range (γ′) order of Na. Despite the complex structural changes, the magnetic behavior of Na1.5VOPO4F0.5 probed by magnetic susceptibility, heat capacity, and electron spin resonance measurements is well described by the regular frustrated square lattice model of the high-temperature α-polymorph. The averaged nearest-neighbor and next-nearest-neighbor couplings are J̅ 1≃−3.7 K and J̅ 2≃6.6 K, respectively. Nuclear magnetic resonance further reveals the long-range ordering at TN=2.6 K in low magnetic fields. Although the experimental data are consistent with the simplified square-lattice description, band structure calculations suggest that the ordering of Na atoms introduces a large number of inequivalent exchange couplings that split the square lattice into plaquettes. Additionally, the direct connection between the vanadium polyhedra induces an unusually strong interlayer coupling having effect on the transition entropy and the transition anomaly in the specific heat. Peculiar features of the low-temperature crystal structure and the relation to isostructural materials suggest Na1.5VOPO4F0.5 as a parent compound for the experimental study of tetramerized square lattices as well as frustrated square lattices with different values of spin.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 47
DOI: 10.1103/PhysRevB.84.014429
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“Phase-slip phenomena in NbN superconducting nanowires with leads”. Elmurodov AK, Peeters FM, Vodolazov DY, Michotte S, Adam S, de Menten de Horne F, Piraux L, Lucot D, Mailly D, Physical review : B : solid state 78, 214519 (2008). http://doi.org/10.1103/PhysRevB.78.214519
Abstract: Transport properties of a superconducting NbN nanowire are studied experimentally and theoretically. Different attached leads (superconducting contacts) allowed us to measure current-voltage (I-V) characteristics of different segments of the wire independently. The experimental results show that with increasing the length of the segment the number of jumps in the I-V curve increases indicating an increasing number of phase-slip phenomena. The system shows a clear hysteresis in the direction of the current sweep, the size of which depends on the length of the superconducting segment. The interpretation of the experimental results is supported by theoretical simulations that are based on the time-dependent Ginzburg-Landau theory, the heat equation has been included in the Ginzbur-Landau theory.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 27
DOI: 10.1103/PhysRevB.78.214519
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“Phase transition and magnetic anisotropy of (La,Sr)MnO3 thin films”. Wang Z-H, Kronmüller H, Lebedev OI, Gross GM, Razavi FS, Habermeier HU, Shen BG, Physical review : B : condensed matter and materials physics 65, 054411 (2002). http://doi.org/10.1103/PhysRevB.65.054411
Abstract: The magnetic proper-ties and their correlation with the microstructure and electrical transport are investigated in La0.88Sr0.1MnO3 films grown on (100)SrTiO3 Single crystal substrates with thickness ranging from 100 to 2500 Angstrom. The ultrathin film (t = 100 Angstrom) has a single ferromagnetic transition (FMT) at T-c of 250 K, whereas the thicker films exhibit two FMTs, with the main one at a lowered T-c of 200 K while the minor one around 300 K. Furthermore, a thickness dependent magnetic anisotropy has been found, strongly indicating the existence of strain effect, which is also revealed by the transmission electron microscopy study. The suppressed Jahn-Teller distortion (JTD) by the epitaxial strain, and the recovered JTD due to the strain relexation are suggested to explain the metallic behavior in thin films and the insulating behavior in the thick film (t = 2500 Angstrom), repectively.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 23
DOI: 10.1103/PhysRevB.65.054411
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“Phase transitions in thin mesoscopic superconducting disks”. Schweigert VA, Peeters FM, Physical review : B : condensed matter and materials physics 57, 13817 (1998). http://doi.org/10.1103/PhysRevB.57.13817
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 200
DOI: 10.1103/PhysRevB.57.13817
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“Phonon dispersions and piezoelectricity in bulk and multilayers of hexagonal boron nitride”. Michel KH, Verberck B, Physical review : B : condensed matter and materials physics 83, 115328 (2011). http://doi.org/10.1103/PhysRevB.83.115328
Abstract: A unified theory of phonon dispersions and piezoelectricity in bulk and multilayers of hexagonal boron nitride (h-BN) is derived. The dynamical matrix is calculated on the basis of an empirical force constant model of intralayer valence and interlayer van der Waals interactions. Coulomb interactions are calculated by Ewalds method, adapted for the three-dimensional (3D) and the multilayer case. The deformation of the ionic charge distribution with long-wave lattice displacements is taken into account. Special attention is devoted to the nonanalytic long-range Coulomb contribution to the dynamical matrix which is different for the 3D crystal and the multilayer case. Consequently there is a splitting of the transverse optical (TO) and longitudinal optical (LO) phonon branches of E1u symmetry and a discontinuity of the A2u branch at the Γ point in 3D h-BN. No such splitting and discontinuity at Γ are present in multilayer crystals with a finite number N of layers. There a diverging bundle of N overbending optical phonon branches emerges from Γ. Borns long-wave theory is applied and extended for the study of piezoelectricity in layered crystals. While 3D h-BN and h-BN multilayers with an even number of layers (symmetry D6h) are not piezoelectric, multilayers with an uneven number of Nu layers (symmetry D3h) are piezoelectric; the piezoelectric coefficient e1,11 is inversely proportional to Nu.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 82
DOI: 10.1103/PhysRevB.83.115328
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“Phonon-induced pure dephasing in exciton-biexciton quantum dot systems driven by ultrafast laser pulse sequences”. Axt VM, Kuhn T, Vagov A, Peeters FM, Physical review : B : condensed matter and materials physics 72, 125309 (2005). http://doi.org/10.1103/PhysRevB.72.125309
Abstract: A semiconductor quantum dot model accounting for single exciton as well as biexciton states coupled to phonons and laser light is investigated in the limit of strong electronic confinement. For an arbitrary sequence of excitations with ultrafast pulses analytical solutions are obtained for all density-matrix elements. The results are nonperturbative with respect to both the carrier-phonon and the carrier-light coupling. Numerical results for a single pulse excitation are presented illustrating spectral features of our solution as well as pulse area and temperature dependences.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 48
DOI: 10.1103/PhysRevB.72.125309
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“Phonon softening and direct to indirect band gap crossover in strained single-layer MoSe2”. Horzum S, Sahin H, Cahangirov S, Cudazzo P, Rubio A, Serin T, Peeters FM, Physical review : B : condensed matter and materials physics 87, 125415 (2013). http://doi.org/10.1103/PhysRevB.87.125415
Abstract: Motivated by recent experimental observations of Tongay et al. [Nano Lett. 12, 5576 (2012)] we show how the electronic properties and Raman characteristics of single layer MoSe2 are affected by elastic biaxial strain. We found that with increasing strain: (1) the E' and E '' Raman peaks (E-2g and E-1g in bulk) exhibit significant redshifts (up to similar to 30 cm(-1)), (2) the position of the A'(1) peak remains at similar to 180 cm(-1) (A(1g) in bulk) and does not change considerably with further strain, (3) the dispersion of low energy flexural phonons crosses over from quadratic to linear, and (4) the electronic band structure undergoes a direct to indirect band gap crossover under similar to 3% biaxial tensile strain. Thus the application of strain appears to be a promising approach for a rapid and reversible tuning of the electronic, vibrational, and optical properties of single layer MoSe2 and similar MX2 dichalcogenides. DOI:10.1103/PhysRevB.87.125415
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 171
DOI: 10.1103/PhysRevB.87.125415
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“Photoluminescence of negatively charged excitons in high magnetic fields”. Hayne M, Jones CL, Bogaerts R, Riva C, Usher A, Peeters FM, Herlach F, Moshchalkov VV, Henini M, Physical review : B : condensed matter and materials physics 59, 2927 (1999). http://doi.org/10.1103/PhysRevB.59.2927
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 86
DOI: 10.1103/PhysRevB.59.2927
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“Piezoelectric surface acoustical phonon limited mobility of electrons in graphene on a GaAs substrate”. Zhang SH, Xu W, Badalyan SM, Peeters FM, Physical review : B : condensed matter and materials physics 87, 075443 (2013). http://doi.org/10.1103/PhysRevB.87.075443
Abstract: We study the mobility of Dirac fermions in monolayer graphene on a GaAs substrate, limited by the combined action of the extrinsic potential of piezoelectric surface acoustical phonons of GaAs (PA) and of the intrinsic deformation potential of acoustical phonons in graphene (DA). In the high-temperature (T) regime, the momentum relaxation rate exhibits the same linear dependence on T but different dependencies on the carrier density n, corresponding to the mobility mu proportional to 1 root n and 1/n, respectively for the PA and DA scattering mechanisms. In the low-T Bloch-Gruneisen regime, the mobility shows the same square-root density dependence mu proportional to root n, but different temperature dependencies mu proportional to T-3 and T-4, respectively for PA and DA phonon scattering. DOI: 10.1103/PhysRevB.87.075443
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 25
DOI: 10.1103/PhysRevB.87.075443
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“Pillars as antipinning centers in superconducting films”. Berdiyorov GR, Misko VR, Milošević, MV, Escoffier W, Grigorieva IV, Peeters FM, Physical review : B : condensed matter and materials physics 77, 024526 (2008). http://doi.org/10.1103/PhysRevB.77.024526
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 35
DOI: 10.1103/PhysRevB.77.024526
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“Pinning and depinning of a classic quasi-one-dimensional Wigner crystal in the presence of a constriction”. Piacente G, Peeters FM, Physical review : B : condensed matter and materials physics 72, 205208 (2005). http://doi.org/10.1103/PhysRevB.72.205208
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 46
DOI: 10.1103/PhysRevB.72.205208
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“Plasmon and coupled plasmon-phonon modes in graphene in the presence of a driving electric field”. Zhao CX, Xu W, Dong HM, Peeters FM, Physical review : B : condensed matter and materials physics 89, 195447 (2014). http://doi.org/10.1103/PhysRevB.89.195447
Abstract: We present a theoretical study of the plasmon and coupled plasmon-phonon modes induced by intraband electron-electron interaction in graphene in the presence of driving dc electric field. We find that the electric field dependence of these collective excitation modes in graphene differs significantly from that in a conventional two-dimensional electron gas with a parabolic energy spectrum. This is due mainly to the fact that graphene has a linear energy spectrum and the Fermi velocity of electrons in graphene is much larger than the drift velocity of electrons. The obtained results demonstrate that the plasmon and coupled plasmon-phonon modes in graphene can be tuned by applying not only the gate voltage but also the source-to-drain field. The manipulation of plasmon and coupled plasmon-phonon modes by source-to-drain voltage can let graphene be more conveniently applied as an advanced plasmonic material.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 9
DOI: 10.1103/PhysRevB.89.195447
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“Plasmonic excitations in Coulomb-coupled N-layer graphene structures”. Zhu J-J, Badalyan SM, Peeters FM, Physical review : B : condensed matter and materials physics 87, 085401 (2013). http://doi.org/10.1103/PhysRevB.87.085401
Abstract: We study Dirac plasmons and their damping in spatially separated N-layer graphene structures at finite doping and temperatures. The plasmon spectrum consists of one optical excitation with square-root dispersion and N – 1 acoustical excitations with linear dispersion, which are undamped at zero temperature and finite doping within a triangular energy region outside the electron-hole continuum. In the long-wavelength limit the energy and weight of the optical plasmon modes increase, respectively, as the square root and linearly with N in agreement with recent experimental findings. The energy and weight of the upper-lying acoustical branches also increase with N. This increase is strongest for the uppermost acoustical mode, and we find that its energy can exceed at some value of momentum the plasmon energy in an individual graphene sheet. Meanwhile, the energy of the low-lying acoustical branches decreases weakly with N as compared with the single acoustical mode in double-layer graphene structures. Our numerical calculations provide a detailed understanding of the overall behavior of the wave-vector dependence of the optical and acoustical multilayer plasmon modes and show how their dispersion and damping are modified as a function of temperature, interlayer spacing, and inlayer carrier density in (un)balanced graphene multilayer structures. DOI: 10.1103/PhysRevB.87.085401
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 59
DOI: 10.1103/PhysRevB.87.085401
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“Polaron-cyclotron-resonance spectrum resulting from interface- and slab-phonon modes in a GaAs/AlAs quantum well”. Hai GQ, Peeters FM, Devreese JT, Physical review : B : condensed matter and materials physics 47, 10358 (1993). http://doi.org/10.1103/PhysRevB.47.10358
Abstract: The effects of interface optical-phonon and confined slab LO-phonon modes on the polaron cyclotron-resonance frequency are investigated for a GaAs/AlAs quantum well. Using degenerate second-order perturbation theory, the polaron Landau levels are calculated and the polaron resonant region is investigated. In order to know the relative importance of the different resonant frequencies we present a full calculation of the magneto-optical absorption spectrum. At a fixed magnetic field we found four different peaks in the absorption spectrum. The relative oscillator strength of the different peaks changes with increasing magnetic field. For comparative purposes, the polaron Landau levels and cyclotron mass are also calculated using only the bulk LO-phonon modes. The influence of the finiteness of the confinement potential is investigated. We found that the interface-phonon modes influence the magnetopolaron resonance considerably near the optical-phonon frequencies for narrow wells. In the limit of zero magnetic field we recover our previous results and in the case of an infinite-barrier quantum well we are able to recover the results for a two- and three-dimensional system.
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.736
Times cited: 69
DOI: 10.1103/PhysRevB.47.10358
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“Polaron effect on D- centers in weakly polar semiconductors”. Shi JM, Peeters FM, Farias GA, Freire JAK, Hai GQ, Devreese JT, Bednarek S, Adamowski J, Physical review : B : condensed matter and materials physics 57, 3900 (1998). http://doi.org/10.1103/PhysRevB.57.3900
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.836
Times cited: 28
DOI: 10.1103/PhysRevB.57.3900
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“Polaron effects in electron channels on a helium film”. Farias GA, Costa Filho RN, Peeters FM, Studart N, Physical review : B : condensed matter and materials physics 64, 104301 (2001). http://doi.org/10.1103/PhysRevB.64.104301
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 2
DOI: 10.1103/PhysRevB.64.104301
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“Polaron impurity states on a liquid helium film”. Farias GA, Peeters FM, Physical review : B : condensed matter and materials physics 55, 3763 (1997)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 8
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“Portlandite crystal : bulk, bilayer, and monolayer structures”. Aierken Y, Sahin H, Iyikanat F, Horzum S, Suslu A, Chen B, Senger RT, Tongay S, Peeters FM, Physical review : B : condensed matter and materials physics 91, 245413 (2015). http://doi.org/10.1103/PhysRevB.91.245413
Abstract: Ca(OH)(2) crystals, well known as portlandite, are grown in layered form, and we found that they can be exfoliated on different substrates. We performed first principles calculations to investigate the structural, electronic, vibrational, and mechanical properties of bulk, bilayer, and monolayer structures of this material. Different from other lamellar structures such as graphite and transition-metal dichalcogenides, intralayer bonding in Ca(OH)(2) is mainly ionic, while the interlayer interaction remains a weak dispersion-type force. Unlike well-known transition-metal dichalcogenides that exhibit an indirect-to-direct band gap crossover when going from bulk to a single layer, Ca(OH)(2) is a direct band gap semiconductor independent of the number layers. The in-plane Young's modulus and the in-plane shear modulus of monolayer Ca(OH)(2) are predicted to be quite low while the in-plane Poisson ratio is larger in comparison to those in the monolayer of ionic crystal BN. We measured the Raman spectrum of bulk Ca(OH)(2) and identified the high-frequency OH stretching mode A(1g) at 3620 cm(-1). In this study, bilayer and monolayer portlandite [Ca(OH)(2)] are predicted to be stable and their characteristics are analyzed in detail. Our results can guide further research on ultrathin hydroxites.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 29
DOI: 10.1103/PhysRevB.91.245413
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“Positively charged magneto-excitons in a semiconductor quantum well”. Riva C, Peeters FM, Varga K, Physical review : B : condensed matter and materials physics 64, 235301 (2001). http://doi.org/10.1103/PhysRevB.64.235301
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 25
DOI: 10.1103/PhysRevB.64.235301
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“Power-law dependence of the angular momentum transition fields in few-electron quantum dots”. Anisimovas E, Matulis A, Tavernier MB, Peeters FM, Physical review : B : condensed matter and materials physics 69, 075305 (2004). http://doi.org/10.1103/PhysRevB.69.075305
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 12
DOI: 10.1103/PhysRevB.69.075305
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“Predicted field-dependent increase of critical currents in asymmetric superconducting nanocircuits”. Clem JR, Mawatari Y, Berdiyorov GR, Peeters FM, Physical review : B : condensed matter and materials physics 85, 144511 (2012). http://doi.org/10.1103/PhysRevB.85.144511
Abstract: The critical current of a thin superconducting strip of width W much larger than the Ginzburg-Landau coherence length xi but much smaller than the Pearl length Lambda = 2 lambda(2)/d is maximized when the strip is straight with defect-free edges. When a perpendicular magnetic field is applied to a long straight strip, the critical current initially decreases linearly with H but then decreases more slowly with H when vortices or antivortices are forced into the strip. However, in a superconducting strip containing sharp 90 degrees or 180 degrees turns, the zero-field critical current at H = 0 is reduced because vortices or antivortices are preferentially nucleated at the inner corners of the turns, where current crowding occurs. Using both analytic London-model calculations and time-dependent Ginzburg-Landau simulations, we predict that in such asymmetric strips the resulting critical current can be increased by applying a perpendicular magnetic field that induces a current-density contribution opposing the applied current density at the inner corners. This effect should apply to all turns that bend in the same direction.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 40
DOI: 10.1103/PhysRevB.85.144511
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“Progressive melting in confined one-dimensional C60 chains”. Bousige C, Rols S, Paineau E, Rouziere S, Mocuta C, Verberck B, Wright JP, Kataura H, Launois P, Physical review : B : condensed matter and materials physics 86, 045446 (2012). http://doi.org/10.1103/PhysRevB.86.045446
Abstract: C-60 fullerenes confined inside single-walled carbon nanotubes form an archetypal one-dimensional system. X-ray diffraction experiments, from room temperature to 1073 K, reveal an increasing melting phenomenon. Detailed analysis of the sawtooth peak characteristic of the fullerene organization allows the quantitative determination of fluctuations in intermolecular distances. The present results validate the predictions of one-dimensional statistical models.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
DOI: 10.1103/PhysRevB.86.045446
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“Properties of two-dimensional Coulomb clusters confined in a ring”. Schweigert IV, Schweigert VA, Peeters FM, Physical review : B : condensed matter and materials physics 54, 10827 (1996). http://doi.org/10.1103/PhysRevB.54.10827
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.736
Times cited: 27
DOI: 10.1103/PhysRevB.54.10827
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“Proximity induced metal-insulator transition in YBa2Cu3O7/La2/3Ca1/3MnO3 superlattices”. Holden T, Habermeier H-U, Cristiani G, Golnik A, Boris A, Pimenov A, Humlicek J, Lebedev OI, Van Tendeloo G, Keimer B, Bernhard C, Physical review : B : condensed matter and materials physics 69, 064505 (2004). http://doi.org/10.1103/PhysRevB.69.064505
Abstract: The far-infrared dielectric response of superlattices (SL) composed of superconducting YBa2Cu3O7 (YBCO) and ferromagnetic La0.67Ca0.33MnO3 (LCMO) has been investigated by ellipsometry. A drastic decrease of the free-carrier response is observed which involves an unusually large length scale of d(crit)approximate to20 nm in YBCO and d(crit)approximate to10 nm in LCMO. A corresponding suppression of metallicity is not observed in SL's where LCMO is replaced by the paramagnetic metal LaNiO3. Our data suggest that either a long-range charge transfer from the YBCO to the LCMO layers or alternatively a strong coupling of the charge carriers to the different and competitive kind of magnetic correlations in the LCMO and YBCO layers is at the heart of the observed metal-insulator transition. The low free-carrier response observed in the far-infrared dielectric response of the magnetic superconductor RuSr2GdCu2O8 is possibly related to this effect.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 101
DOI: 10.1103/PhysRevB.69.064505
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“Proximity-induced pseudogap in mesoscopic superconductor/normal-metal bilayers”. Zha G-Q, Covaci L, Zhou S-P, Peeters FM, Physical review : B : condensed matter and materials physics 82, 140502 (2010). http://doi.org/10.1103/PhysRevB.82.140502
Abstract: Recent scanning tunneling microscopy (STM) measurements of the proximity effect in Au/La2−xSrxCuO4 and La1.55Sr0.45CuO4/La2−xSrxCuO4 bilayers showed a proximity-induced pseudogap [O. Yuli, I. Asulin, Y. Kalcheim, G. Koren, and O. Millo, Phys. Rev. Lett. 103, 197003 (2009)]. We describe the proximity effect in mesoscopic superconductor/normal-metal bilayers by using the Bogoliubov-de Gennes equations for a tight-binding Hamiltonian with competing antiferromagnetic and d-wave superconductivity orders. The temperature-dependent local density of states is calculated as a function of the distance from the interface. Bound state due to both d-wave and spin-density wave gaps are formed in the normal metal for energies less than the respective gaps. If there is a mismatch between the Fermi velocities in the two layers we observe that these states will shift in energy when spin-density wave order is present, thus inducing a minigap at finite energy. We conclude that the STM measurement in the proximity structures is able to distinguish between the two scenarios proposed for the pseudogap (competing or precursor to superconductivity).
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 7
DOI: 10.1103/PhysRevB.82.140502
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“Quantum and transport conductivities in monolayer graphene”. Dong HM, Xu W, Zeng Z, Lu TC, Peeters FM, Physical review : B : condensed matter and materials physics 77, 235402 (2008). http://doi.org/10.1103/PhysRevB.77.235402
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 31
DOI: 10.1103/PhysRevB.77.235402
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“Quantum rings as electron spin beam splitters”. Földi P, Kálmán O, Benedict MG, Peeters FM, Physical review : B : condensed matter and materials physics 73, 155325 (2006). http://doi.org/10.1103/PhysRevB.73.155325
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 145
DOI: 10.1103/PhysRevB.73.155325
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“Quantum rings with time-dependent spin-orbit coupling: Spintronic Rabi oscillations and conductance properties”. Földi P, Benedict MG, Kalman O, Peeters FM, Physical review : B : solid state 80, 165303 (2009). http://doi.org/10.1103/PhysRevB.80.165303
Abstract: The strength of the (Rashba-type) spin-orbit coupling in mesoscopic semiconductor rings can be tuned with external gate voltages. Here we consider the case of a periodically changing spin-orbit interaction strength in time as induced by sinusoidal voltages. In a closed one dimensional quantum ring with weak spin-orbit coupling, Rabi oscillations are shown to appear. We find that the time evolution of initially localized wave packets exhibits a series of collapse and revival phenomena. Partial revivalsthat are typical in nonlinear systemsare shown to correspond to superpositions of states localized at different spatial positions along the ring. These spintronic Schrödinger-cat states appear periodically, and similarly to their counterparts in other physical systems, they are found to be sensitive to disturbances caused by the environment. The time-dependent spin transport problem, when leads are attached to the ring, is also solved. We show that the sideband currents induced by the oscillating spin-orbit interaction strength can become the dominant output channel, even in the presence of moderate thermal fluctuations and random scattering events.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 26
DOI: 10.1103/PhysRevB.80.165303
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