Anders Stroem, University of Gothenburg
The crossover from a Luttinger liquid to a quasi-helical liquid state in a one-dimensional system of interacting electrons has been studied. Strong spin-orbit interaction in combination with a transverse magnetic field leads to a gap for one-half of the conducting modes. In particular, the effect of gap opening by electron localization in the presence of non-magnetic disorder will be discussed. It is shown that the localization length has a nonuniform behavior as a function of the magnetic field. With increasing field, the localization length grows from its zero-field Luttinger-liquid value to a maximum, after which it crosses over to again smaller values corresponding to the localization length of spinless fermions.