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A momentum balance equation is developed to investigate the magnetotransport properties in monolayer molybdenum disulphide when a strong perpendicular magnetic field and a weak in-plane electric field are applied simultaneously. At low temperature, in the presence of intravalley impurity scattering, Shubnikov–de Haas oscillation shows up accompanied by a beating pattern arising from large spin splitting and its period may halve due to the high-order oscillating term at large magnetic field for samples with ultrahigh mobility. In the case of intervalley disorders, there exists a magnetic-field range where the magnetoresistivity almost vanishes. For a low-mobility layer, a phase inversion of oscillating peaks is acquired in accordance with recent experiment. At high temperature when Shubnikov–de Haas oscillation is suppressed, the magnetophonon resonances induced by both optical phonons (mainly due to homopolar and Frohlich modes) and acoustic phonons (mainly due to intravalley transverse and longitudinal acoustic modes) emerge for a suspended system with high mobility. For the single layer on a substrate, another resonance due to surface optical phonons may occur, resulting in a complex behavior of the total magnetoresistance. The beating pattern of magnetophonon resonance due to optical phonons can also be observed. However, for a nonsuspended layer with low mobility, the magnetoresistance oscillation almost disappears and the resistivity increases with field monotonically. [ABSTRACT FROM AUTHOR]

A balance-equation scheme is developed to investigate the magnetotransport in a dc current biased graphene. We examine the Shubnikov-de Haas oscillation under a nonzero bias current. With an increase in the current density, the oscillatory differential resistivity exhibits phase inversion, in agreement with recent experimental observation. In the presence of surface optical phonons, a second phase inversion may occur at higher dc bias due to the reduced influence of electron heating and the enhanced direct effect of current on differential magnetoresistivity. We also predict the appearance of current-induced magnetoresistance oscillation in suspended graphene at lower magnetic fields and larger current densities. For the graphene mobility currently available (≈20 m2/V s), the oscillatory behavior may be somewhat altered by magnetophonon resonance arising from intrinsic acoustic phonon under finite bias current conditions. [ABSTRACT FROM AUTHOR]

We examine the effect of changing the linear polarization angle θ of incident microwaves with respect to the dc current on radiation-induced magnetoresistance oscillations in a two-dimensional (2D) system within the balance-equation formulation of the photon-assisted magnetotransport model, considering the radiative decay as the sole damping mechanism. At an extremum the amplitude of oscillatory magnetoresistance Rxx exhibits a sinusoidal, up to a factor of 5, magnitude variation with rotating the polarization angle θ. The maximal amplitude shows up generally at a nonzero θ, which is dependent upon the extremum in question, the 2D electron setup, the radiation frequency, and the magnetic field orientation. These results provide a natural explanation for the experimental observations by Mani et al. [ Phys. Rev. B 84 085308 (2011)] and Ramanayaka et al. [ Phys. Rev. B 85 205315 (2012)]. [ABSTRACT FROM AUTHOR]

We examine the nonlinear magnetoresistance oscillations in a dc-biased high-mobility two-dimensional electron system irradiated by intense microwaves with a current-controlled balance-equation model for multi-photon-assisted magnetotransport. It is shown that the maxima/minima positions, particularly the oscillation period of the differential resistance as a function of the ratio of the microwave frequency ω to the cyclotron frequency ωc, strongly depend on the radiation intensity under a large bias dc current density. Theoretical predictions well reproduce the recent experimental findings by Khodas et al. Phys. Rev. Lett. 104 206801 (2010), and support the multiphoton origin of these unusual magnetoresistance oscillations. [ABSTRACT FROM AUTHOR]

Considering finite-temperature screened electron-impurity scattering, we present a kinetic equation approach to investigate transport properties of two-dimensional massive fermions in silicene. We find that the longitudinal conductivity is always nonvanishing when chemical potential lies within the energy gap. This residual conductivity arises from interband correlation and strongly depends on strength of electron-impurity scattering. We also clarify that the electron-impurity interaction makes substantial contributions to the spin and valley Hall conductivities, which, however, are almost independent of impurity density. The dependencies of longitudinal conductivity as well as of spin and valley Hall conductivities on chemical potential, temperature, and gap energy are analyzed. [ABSTRACT FROM AUTHOR]

We study the full counting statistics (FCS) of electron tunneling through a multiterminal quantum dot in the Kondo regime within the slave-boson mean-field theory. By employing the method of Gogolin and Komnik for calculating the FCS generating function based on the nonequilibrium Green's function [Phys. Rev. B 73, 195301 (2006)]. we obtain the counting field λ-dependent self-consistent equations for the mean values of the slave-boson fields and the explicit expression for the derivative of the adiabatic potential of the system with respect to the counting fields. Performing a perturbative expansion to the first order of λ, we find an extra contribution to the shot noise due to the bias-induced Bose field fluctuation, and then confirm that the nonequilibrium particle number fluctuation plays an important role in the current noise of the Kondo dot: enhancement of the current autocorrelation and a positive current cross-correlation. [ABSTRACT FROM AUTHOR]