Charge transfer statistics in symmetric fractional edge-state Mach-Zehnder interferometer
V. V. Ponomarenko and D. V. Averin
We have studied the zero-temperature statistics of charge transfer between the two edges of quantum Hall liquids with filling factors nu=1/(2m+1) forming Mach-Zehnder interferometer. The known Bethe ansatz solution for symmetric interferometer is used to obtain the cumulant-generating function of ch ... [Phys. Rev. B 80, 201313 (2009)] published Fri Nov 20, 2009.
Flux pinning properties in BaMO (M=Zr,Sn) nanorod-introduced ErBaCuO films
Satoshi Awaji, Masafumi Namba, Kazuo Watnabe, Shun Ito, Eiji Aoyagi et al.
Flux pinning properties on the ErBaCaO films with the nanoscaled and columnar-shaped BaMO (BMO,M=Zr,Sn) precipitates, i.e., nanorods, were investigated systematically based on the microstructure, critical current density J and irreversibility field B properties in high magnetic fields. We found that ... [J. Appl. Phys. 106, 103915 (2009)] published Fri Nov 20, 2009.
Terahertz photoresponse of a quantum Hall edge-channel diode
Christian Notthoff, Kevin Rachor, Detlef Heitmann, and Axel Lorke
The terahertz (THz) photoresponse of a two-dimensional electron gas in the quantum Hall regime is investigated. We use a sample structure which is topologically equivalent to a Corbino geometry combined with a cross-gate technique. This quasi-Corbino geometry allows us to directly investigate the TH ... [Phys. Rev. B 80, 205320 (2009)] published Thu Nov 19, 2009.
Local Current Injection into Mesoscopic Superconductors for the Manipulation of Quantum States
M. V. Milosevic, A. Kanda, S. Hatsumi, F. M. Peeters, and Y. Ootuka
We perform strategic current injection in a small mesoscopic superconductor and control the (non)equilibrium quantum states in an applied homogeneous magnetic field. In doing so, we realize a current-driven splitting of multiquanta vortices, current-induced transitions between states with different ... [Phys. Rev. Lett. 103, 217003 (2009)] published Thu Nov 19, 2009.
Effects of repulsive and attractive ionized impurities on the resistivity of semiconductor heterostructures in the quantum Hall regime
A. Raymond, I. Bisotto, Y. M. Meziani, S. Bonifacie, C. Chaubet et al.
We have investigated experimentally and theoretically the effect of repulsive and attractive ionized impurities on the resistivity components (rho and rho) in the quantum Hall effect regime. GaAs/GaAlAs asymmetric modulation-doped quantum wells with additional delta doping (by Si donor atoms or Be a ... [Phys. Rev. B 80, 195316 (2009)] published Wed Nov 18, 2009.
Bilayer quantum Hall system at nu=1: Pseudospin models and in-plane magnetic field
O. Tieleman, A. Lazarides, D. Makogon, and C. Morais Smith
We investigate two theoretical pseudomagnon-based models for a bilayer quantum Hall system (BQHS) at total filling factor nu=1. We find a unifying framework which elucidates the different approximations that are made. We also consider the effect of an in-plane magnetic field in BQHSs at nu=1, by der ... [Phys. Rev. B 80, 205315 (2009)] published Tue Nov 17, 2009.
Local density of states of electron-crystal phases in graphene in the quantum Hall regime
O. Poplavskyy, M. O. Goerbig, and C. Morais Smith
We calculate, within a self-consistent Hartree-Fock approximation, the local density of states for different electron crystals in graphene subject to a strong magnetic field. We investigate both the Wigner crystal and bubble crystals with M electrons per lattice site. The total density of states con ... [Phys. Rev. B 80, 195414 (2009)] published Tue Nov 17, 2009.
Transverse instabilities of multiple vortex chains in magnetically coupled NbSe/permalloy superconductor/ferromagnet bilayers
G. Karapetrov, M. V. Milosevic, M. Iavarone, J. Fedor, A. Belkin et al.
Using scanning tunneling microscopy and Ginzburg-Landau simulations, we explore vortex configurations in magnetically coupled NbSe/permalloy superconductor/ferromagnet bilayer. The permalloy film with stripe domain structure induces periodic local magnetic induction in the superconductor, creating a ... [Phys. Rev. B 80, 180506 (2009)] published Mon Nov 16, 2009.
Nonlinear transport theory for negative-differential resistance states of two-dimensional electron systems in strong magnetic fields
A. Kunold and M. Torres
We present a model to describe the nonlinear response to a direct dc current applied to a two-dimensional electron system in a strong magnetic field. The model is based on the solution of the von Neumann equation incorporating the exact dynamics of two-dimensional damped electrons in the presence of ... [Phys. Rev. B 80, 205314 (2009)] published Fri Nov 13, 2009.
Edge-State Velocity and Coherence in a Quantum Hall Fabry-Perot Interferometer
D. T. McClure, Yiming Zhang, B. Rosenow, E. M. Levenson-Falk, C. M. Marcus et al.
We investigate nonlinear transport in electronic Fabry-Perot interferometers in the integer quantum Hall regime. For interferometers sufficiently large that Coulomb blockade effects are absent, a checkerboardlike pattern of conductance oscillations as a function of dc bias and perpendicular magnetic ... [Phys. Rev. Lett. 103, 206806 (2009)] published Fri Nov 13, 2009.
Three-Dimensional Topological Insulators on the Pyrochlore Lattice
H.-M. Guo and M. Franz
Electrons hopping on the sites of a three-dimensional pyrochlore lattice are shown to form topologically nontrivial insulating phases when the spin-orbit (SO) coupling and lattice distortions are present. Of 16 possible topological classes 9 are realized for various parameters in this model. Specifi ... [Phys. Rev. Lett. 103, 206805 (2009)] published Fri Nov 13, 2009.
Effect of electron-electron scattering on magnetointersubband resistance oscillations of two-dimensional electrons in GaAs quantum wells
A. V. Goran, A. A. Bykov, A. I. Toropov, and S. A. Vitkalov
The low-temperature (4.2
Gap opening in the zeroth Landau level of graphene
A. J. M. Giesbers, L. A. Ponomarenko, K. S. Novoselov, A. K. Geim, M. I. Katsnelson et al.
We have measured a strong increase of the low-temperature resistivity rho and a zero-value plateau in the Hall conductivity sigma at the charge neutrality point in graphene subjected to high magnetic fields up to 30 T. We explain our results by a simple model involving a field dependent splitting of ... [Phys. Rev. B 80, 201403 (2009)] published Wed Nov 11, 2009.
Anatomy of Abelian and Non-Abelian Fractional Quantum Hall States
B. Andrei Bernevig and N. Regnault
We deduce a new set of symmetries and relations between the coefficients of the expansion of Abelian and non-Abelian fractional quantum Hall (FQH) states in free (bosonic or fermionic) many-body states. Our rules allow us to build an approximation of a FQH model state with an overlap increasing with ... [Phys. Rev. Lett. 103, 206801 (2009)] published Tue Nov 10, 2009.
Quantum phase transition in Hall conductivity on an anisotropic kagome lattice
Shun-Li Yu, Jian-Xin Li, and Li Sheng
We study theoretically the quantum Hall effect (QHE) on the kagome lattice with anisotropy in one of the hopping integrals. We find an interesting quantum phase, in which the QHE exhibits the energy spectrum given by E(n)=vsqrt((n + 1/2)[h-bar]Be) (n is an integer) being different from the known typ ... [Phys. Rev. B 80, 193304 (2009)] published Thu Nov 5, 2009.
Surface States of Topological Insulators: The Dirac Fermion in Curved Two-Dimensional Spaces
Dung-Hai Lee
The surface of a topological insulator is a closed two-dimensional manifold. The surface states are described by the Dirac Hamiltonian in curved two-dimensional spaces. For a slablike sample with a magnetic field perpendicular to its top and bottom surfaces, there are chiral states delocalized on th ... [Phys. Rev. Lett. 103, 196804 (2009)] published Thu Nov 5, 2009.
Change in the character of quasiparticles without gap collapse in a model of fractional quantum Hall effect
Csaba Tőke and Jainendra K. Jain
It is commonly assumed in the studies of the fractional quantum Hall effect that the physics of a fractional quantum Hall state, in particular the character of its excitations, is invariant under a continuous deformation of the Hamiltonian during which the gap does not close. We show in this article ... [Phys. Rev. B 80, 205301 (2009)] published Wed Nov 4, 2009.
Fractional Topological Insulators
Michael Levin and Ady Stern
We analyze generalizations of two-dimensional topological insulators which can be realized in interacting, time reversal invariant electron systems. These states, which we call fractional topological insulators, contain excitations with fractional charge and statistics in addition to protected edge ... [Phys. Rev. Lett. 103, 196803 (2009)] published Wed Nov 4, 2009.
Interaction-tuned compressible-to-incompressible phase transitions in quantum Hall systems
Z. Papic, N. Regnault, and S. Das Sarma
We analyze transitions between quantum Hall ground states at prominent filling factors nu in the spherical geometry by tuning the width parameter of the Zhang-Das Sarma interaction potential. We find that incompressible ground states evolve adiabatically under this tuning, whereas the compressible o ... [Phys. Rev. B 80, 201303 (2009)] published Mon Nov 2, 2009.
Anomalous finite size effects on surface states in the topological insulator BiSe
Jacob Linder, Takehito Yokoyama, and Asle Sudbo
We study how the surface states in the strong topological insulator BiSe are influenced by finite size effects and compare our results with those recently obtained for two-dimensional topological insulator HgTe. We demonstrate two important distinctions: (i) contrary to HgTe, the surface states in B ... [Phys. Rev. B 80, 205401 (2009)] published Mon Nov 2, 2009.
Local density of states in disordered two-dimensional electron gases at high magnetic field
Thierry Champel and Serge Florens
Motivated by high-accuracy scanning tunneling spectroscopy measurements on disordered two-dimensional electron gases in strong magnetic field, we present an expression for the local density of states (LDoS) of electrons moving in a smooth arbitrary potential landscape on the scale of the magnetic le ... [Phys. Rev. B 80, 161311 (2009)] published Wed Oct 28, 2009.