抄録
The localization problem in a three dimensional tight binding system in the presence of a spatially random vector potential is investigated. The density of states exhibits tails of localized states that are induced by large regions in space where the vector potential is accidentally constant. In the center of the band the states are shown to be extended by investigating the system size dependence of the inverse participation number. The existence of a metal-insulator transition at a critical energy with non-vanishing density of states is demonstrated. The system size and energy dependent exponential decay length of the modulus of the Green's function satisfies a one-parameter scaling law. The value of the critical exponent is estimated, ν ≈ 1, which is different from those found previously for the disordered tight binding (Anderson) model with and without homogeneous magnetic field.
