Effect of mass anisotropy on the low temperature conductivity of disordered systems in two dimensions

Abstract

The conductivity of an anistropic 2D disordered system (e.g. (110) Si inversion layer) is shown to depend logarithmically on the length scale, as for isotropic systems, though with altered coefficients of the logarithmic term. Within the scaling theory of localization, the ratio of the coefficients along the two principal axes is found to vary inversely with the mass anisotropy, independent of the anisotropy of the relaxation time. Comparison is made with the corresponding result obtained assuming only Coulomb interaction effects.