相关论文: Scaling Behavior and Variable Hopping Conductivity…
We report an experimental study of quantum conductivity corrections in a low mobility, high density two-dimensional electron gas in a AlGaAs/GaAs/AlGaAs quantum well in a wide temperature range (1.5K - 110K). This temperature range covers…
The variable range hopping (VRH) model has been widely applied to describe electrical transport in disordered systems, providing theoretical formulas to fit temperature-dependent electric conductivity. These models rely on oversimplified…
The longstanding problem of the Hall resistivity rho(x,y) in the Hall insulator phase is addressed using four-lead Chalker-Coddington networks. Electron interaction effects are introduced via a finite dephasing length. In the quantum…
We study the plateaux of the integer quantum Hall resistance in a bilayer electron system in tilted magnetic fields. In a narrow range of tilt angles and at certain magnetic fields, the plateau level deviates appreciably from the quantized…
High-frequency (HF) conductivity ($\sigma_{hf}$) measured by an acoustical method has been studied in GaAs/AlGaAs heterostructures in a linear and nonlinear regime on acoustic power. It has been shown that in the quantum Hall regime at…
At low temperatures the phase diagram for the quantum Hall effect has a powerful symmetry arising from the Law of Corresponding States. This symmetry gives rise to an infinite order discrete group which is a generalisation of…
We report on the longitudinal and Hall resistivities of a HgTe quantum well with inverted energy spectrum (dQW = 20.3 nm) measured in the quantum Hall (QH) regime at magnetic fields up to 9 T and temperatures 2-50 K. The temperature…
Continued improvement of heat control in mesoscopic conductors brings novel tools for probing strongly correlated electron phenomena. Motivated by these advances, we comprehensively study transport due to a temperature bias in a quantum…
Based on a thermodynamic approach, we have calculated the resistivity of a 2D electron gas, assumed $dissipationless$ in a strong quantum limit. Standard measurements, with extra current leads, define the resistivity caused by a combination…
Thermal transport in solids changes its nature from phonon propagation that suffers from perturbative scattering to thermally activated hops between localized vibrational modes as the level of disorder increases. Models have been proposed…
The high-frequency conductivity of Si delta-doped GaAs/AlGaAs heterostructures is studied in the integer quantum Hall effect (QHE) regime, using acoustic methods. Both the real and the imaginary parts of the complex conductivity are…
The transition from the quantum Hall state to the insulator is considered for non-interacting electrons in a two-dimensional disordered lattice model with perpendicular magnetic field. Using correlated random disorder potentials the…
We study numerically conductance fluctuations near the integer quantum Hall effect plateau transition. The system is presumed to be in a mesoscopic regime, with phase coherence length comparable to the system size. We focus on a…
We propose a phenomenological model that describes counterflow and drag experiments with quantum Hall bilayers in a \nu_T=1 state. We consider the system consisting of statistically distributed areas with local total filling factors…
On the basis of the Kubo-Luttinger linear response theory combined with the scaling theory of Anderson localization predicting the energy dependence of localization length near the mobility edge, we have studied the thermoelectric response…
Scaling laws and universality are often associated with systems exhibiting emergent phenomena possessing a characteristic energy scale. We report nonequilibrium transport measurements on two different types of single-molecule transistor…
We study the quantum non linear response to an applied electric field $E$ of a one dimensional pinned charge density wave or Luttinger liquid in presence of disorder. From an explicit construction of low lying metastable states and of…
A comprehensive magnetotransport study including resistivity ($\rho_{xx}$) at various fields, isothermal magnetoresistance and Hall resistivity ($\rho_{xy}$) has been carried out at different temperatures on the Co$_{2}$TiAl Heusler alloy.…
For the low-temperature electrical conductance of a disordered {\it quantum insulator} in $d$-dimensions, Mott \cite{mott} had proposed his Variable Range Hopping (VRH) formula, $G(T) = G_0 {\rm exp}[-(T_0/T)^{\gamma}]$, where $G_0$ is a…
The transversal and longitudinal resistance in the quantum Hall effect regime was measured in a Si MOSFET sample in which a slot-gate allows one to vary the electron density and filling factor in different parts of the sample. In case of…