Hall effect at a tunable metal-insulator transition

Journals published by the American Physical Society can be found at http://journals.aps.org/Using a rotating magnetic field, the Hall effect in three-dimensional amorphous GdxSi1-x has been measured in the critical regime of the metal-insulator transition for a constant total magnetic field. The Hall coefficient R-0 is negative, indicating electronlike conductivity, with a magnitude that increases with decreasing conductivity. R-0 diverges at the metal-insulator transition, and displays critical behavior with exponent -1 [R(0)similar to(H-H-C)(-1)]. This dependence is interpreted as a linear decrease in the density of mobile carriers nsimilar toR(0)(-1)similar toH-H-C, indicative of the dominant influence of interaction effects

Spin Hall and spin-diagonal conductivity in the presence of Rashba and Dresselhaus spin-orbit coupling

Journals published by the American Physical Society can be found at http://journals.aps.org/We investigate the spin-current linear response conductivity tensor to an electric field in a paramagnetic two-dimensional electron gas with both Rashba and Dresselhaus spin-orbit coupling in the weak scattering regime within the Born approximation. In the usual sample parameters, and for cross-sectional size smaller than the spin-coherence length, the spin-Hall conductivity depends only on the sign of the difference in magnitude of the Rashba and Dresselhaus coupling except within a narrow window where both coupling strengths are equal. We also find that a spin current is generated in the direction of the driving field for a non-zero Dresselhaus term. Possible experimental setups for its detection, taking into account the finite mobility and typical parameters of current samples, are discussed

Conditional Seq2Seq model for the time-dependent two-level system

We apply the deep learning neural network architecture to the two-level system in quantum optics to solve the time-dependent Schrodinger equation. By carefully designing the network structure and tuning parameters, above 90 percent accuracy in super long-term predictions can be achieved in the case of random electric fields, which indicates a promising new method to solve the time-dependent equation for two-level systems. By slightly modifying this network, we think that this method can solve the two- or three-dimensional time-dependent Schrodinger equation more efficiently than traditional approaches.Comment: 17 pages, 6 figure