Related papers: Universal flow diagram for the magnetoconductance …
The temperature driven flow lines of the Hall and dissipative magnetoconductance data (\sigma_{xy},\sigma_{xx}) are studied in the fractional quantum Hall regime for a 2D electron system in GaAs/Al_{x}Ga_{1-x}As heterostructures. The flow…
Oscillatory variations of the diagonal ($G_{xx}$) and Hall ($G_{xy}$) magnetoconductances are discussed in view of topological scaling effects giving rise to the quantum Hall effect. They occur in a field range without oscillations of the…
Magnetic-field-induced phase transitions were studied with a two-dimensional electron AlGaAs/GaAs system. The temperature-driven flow diagram shows the features of the $\Gamma$(2) modular symmetry, which includes distorted flowlines and…
With minima in the diagonal conductance G_{xx} and in the absolute value of the derivative |dG_{xy}/dB| at the Hall conductance value G_{xy}=e^{2}/h, spin-splitting is observed in the quantum Hall effect of heavily Si-doped GaAs layers with…
Impurities and defects are ubiquitous in topological insulators (TIs) and thus understanding the effects of disorder on electronic transport is important. We calculate the distribution of the random conductance fluctuations $P(G)$ of…
We investigate a transition between a two-dimensional topological insulator conduction state, characterized by a conductance $G=2$ (in fundamental units $e^2/h$) and a Chern insulator with $G=1$, induced by polarized magnetic impurities.…
Gated GaAs/AlGaAs heterostructures were used to determine the low-temperature behavior of the two-dimensional electron gas near filling factor nu=1/2 in the disorder-magnetic-field plane. We identify a line on which sigma_{xy} is…
We study the behavior of the extended states of a two-dimensional electron system in silicon in a magnetic field, B. Our results show that the extended states, corresponding to the centers of different Landau levels, merge with the lowest…
A two-dimensional quantum Hall system is studied for a wide class of potentials including single-body random potentials and repulsive electron-electron interactions. We assume that there exists a non-zero excitation gap above the ground…
We study the temperature flow of conductivities in a gated GaAs two-dimensional electron gas (2DEG) containing self-assembled InAs dots and compare the results with recent theoretical predictions. By changing the gate voltage, we are able…
Transport properties of GaAs/{\delta}<Mn>/GaAs/In\timesGa1-\timesAs/GaAs structures containing InxGa1-xAs (\times {\approx} 0.2) quantum well (QW) and Mn delta layer (DL) with relatively high, about one Mn monolayer (ML) content, are…
We study numerically the edge magnetoconductance of a quantum spin Hall insulator in the presence of quenched nonmagnetic disorder. For a finite magnetic field B and disorder strength W on the order of the bulk gap E_g, the conductance…
We have performed low-temperature transport experiments on a Si/SiGe hole system. The measured transverse and longitudinal condductivities $\sigma_{xx}$ and $\sigma_{xy}$ allow us to study the magnetic-field-induced transitions in the…
The transport properties on the two-dimensional surface of coupled multilayer heterostructures are studied in the integer quantum Hall states. We emphasize the criticality of the surface state and the phase coherent transport properties in…
Layered singlet paired superconductors with disorder and broken time reversal symmetry are studied. The phase diagram demonstrates charge-spin separation in transport. In terms of the average intergrain transmission and the interlayer…
We study the effect of backward scatterings in the tunneling at a point contact between the edges of a second level hierarchical fractional quantum Hall states. A universal scaling dimension of the tunneling conductance is obtained only…
We report a theoretical investigation on the conductance and its fluctuation of three-dimensional topological insulators (3D TI) in $Bi_2Se_3$ and $Sb_2Te_3$ in the presence of disorders. Extensive numerical simulations are carried out. We…
Two dimensional disordered superconductors with broken spin-rotation and time-reversal invariance, e.g. with p_x+ip_y pairing, can exhibit plateaus in the thermal Hall coefficient (the thermal quantum Hall effect). Our numerical simulations…
We consider the bilocal conductivity tensor, the two-probe conductance and its fluctuations for a disordered phase-coherent two-dimensional system of non-interacting electrons in the presence of a magnetic field, including correctly the…
There is considerable experimental evidence for the existence in Quantum Hall systems of an approximate emergent discrete symmetry, $\Gamma_0(2) \subset SL(2,Z)$. The evidence consists of the robustness of the tests of a suite a predictions…