Quantum corrections to the conductivity and Hall coefficient of a two-dimensional electron gas in a dirty Al_xGa_(1-x)As/GaAs/Al_xGa_(1-x)As quantum well: From the diffusive to the ballistic regime

摘要

We report an experimental study of quantum conductivity corrections in a low mobility, high density two-dimensional electron gas in an AlGaAs/GaAs/AlGaAs quantum well in a wide temperature range (1.5-110 K). This temperature range covers both the diffusive and the ballistic interaction regimes for our samples. It has been therefore possible to study the crossover between these regimes for both the longitudinal conductivity and the Hall effect. We perform a parameter-free comparison of our experimental data for the longitudinal conductivity at zero magnetic field, the Hall coefficient, and the magnetoresistivity to the recent theories of interaction-induced corrections to the transport coefficients. A quantitative agreement between these theories and our experimental results has been found.