相关论文: Negative Magnetoresistance in the Nearest-neighbor…
We propose a new mechanism of negative magnetoresistance in non-magnetic granular materials in which electron transport is dominated by hopping between two nearest-neighbor clusters. We study the dependence of magnetoresistance on…
In hopping magnetoresistance of doped insulators, an applied magnetic field shrinks the electron (hole) s-wave function of a donor or an acceptor and this reduces the overlap between hopping sites resulting in the positive magnetoresistance…
We propose a mechanism for negative isotropic magnetoresistance in the hopping regime. It results from a memory effect encrypted into spin correlations that are not taken into account by the conventional theory of hopping conductivity. The…
Magnetoresistance in two-dimensional array of Ge/Si quantum dots was studied in a wide range of zero-magnetic field conductances, where the transport regime changes from hopping to diffusive one. The behavior of magnetoresistance is found…
We show that the tunnel coupling between semiclassical states localized in different minima of a smooth random potential increases when magnetic field is applied. This increase originates from the difference in gauge factors which electron…
We reconsider the theory of magnetoresistance in hopping semiconductors. First, we have shown that the random potential of the background impurities affects significantly preexponential factor of the tunneling amplitude which becomes to be…
We show that, due to the weak ferromagnetism of La$_{2-x}$Sr$_x$CuO$_4$, an external magnetic field leads to a dimensional crossover 2D $\to$ 3D for the in-plane transport. The crossover results in an increase of the hole's localization…
The low temperature (0.5-55 K) conduction of semicontinuous gold film vacuum deposited at T \approx 50 K is studied. The film is near the percolation threshold (thickness 3.25 nm). Its resistance is extremely sensitive to the applied…
Magnetoresistance (MR) of ion irradiated monolayer graphene samples with variable-range hopping (VRH) mechanism of conductivity was measured at temperatures down to $T = 1.8$ K in magnetic fields up to $B = 8$ T. It was observed that in…
The magnetoresistance of a granular superconductor in a strong magnetic field destroying the gap in each grain is considered. It is assumed that the tunneling between grains is sufficiently large such that all conventional effects of…
A universal mechanism for strong magnetic-field effects of nonmagnetic organic semiconductors is presented. A weak magnetic field (less than hundreds mT) can substantially change the charge carrier hopping coefficient between two…
A universal mechanism for strong magnetic-field effects of nonmagnetic organic semiconductors is presented. A weak magnetic field (less than hundreds mT) can substantially change the charge carrier hopping coefficient between two…
We develop a theory of magnetoresistance based on variable-range hopping. An exponentially large, low-field and necessarily positive magnetoresistance effect is predicted in the presence of Hubbard interaction and spin-dynamics under…
We investigate the magneto-conductance (MC) anisotropy in the variable range hopping regime, caused by quantum interference effects in three dimensions. When no spin-orbit scattering is included, there is an increase in the localization…
Large positive (P) magnetoresistance (MR) has been observed in parallel magnetic fields in a single 2D layer in a delta-doped GaAs/AlGaAs heterostructure with a variable-range-hopping (VRH) mechanism of conductivity. Effect of large PMR is…
Negative magnetoresistivity is a special magnetotransport property associated with chiral anomaly in four dimensional chiral anomalous systems, which refers to the transport behavior that the DC longitudinal magnetoresistivity decreases…
Magnetoresistive properties of granular Bi-based HTSC with trapped magnetic fields are investigated in the temperature region near superconducting transition . The effect of trapped field and transport current values and orientations on the…
We propose a kinetic theory of transport in metals embedded with ferromagnetic nanoclusters, describing the dependence of the form of magnetoresistance on anisotropy characteristics of the ensemble of clusters and the influence of the…
We study an effect of moderate magnetic field on variable range hopping conductivity in arrays of ferromagnetic granules separated by tunnel barriers. It is shown that the resulting magnetoresistance can be significantly larger than the…
The transport properties of nematic aerogels, which consist of oriented mullite nanofibers coated with a graphene shell, were studied. It is shown that the magnetoresistance of this system is well approximated by two contributions -…