MAGNETIC-FIELD DEPENDENCE OF THE LOCALIZATION LENGTH IN ANDERSON INSULATORS

Using the conventional scaling approach as well as the renormalization group analysis in d = 2 + epsilon dimensions, we calculate the localization length xi(B) in the presence of a magnetic field B. For the quasi-if) case the results are consistent with a universal increase of xi(B) by a numerical factor when the magnetic field is in the range iota << iota(H) less than or similar to xi (0), iota is the mean free path, iota(H) is the magnetic length root (h) over bar c/eB. However, for d greater than or equal to 2 where the magnetic field does cause delocalization there is no universal relation between xi(B) and xi(0). The effect of spin-orbit interaction is briefly considered as well.