Electron delocalization in disordered films induced by magnetic field and film thickness

Abstract

We have studied the delocalization transition of noninteracting electrons in disordered thin films induced by magnetic field and film thickness. We also report results for two-dimensional systems. We have used for this purpose (i) a numerical technique based on transfer-matrix method for quasi-one-dimensional systems; (ii) self-consistent theory of localization for weak fields generalized to situations lacking time-reversal invariance. Numerical results provide strong evidence for a zero-temperature insulator-to-metal transition (MIT) with both field and film thickness. In self-consistent theory we adopt two procedures which give different results on MIT induced by field, temperature, and thickness. The variance between numerical and analytical results is analyzed.