Transport properties of double quantum wires in a magnetic field

The electronic transport properties of disordered double quantum wires are investigated. Application of a magnetic field perpendicular to the axis of the wire leads to the strong suppression of backscattering from disorder at the energies inside the partial energy gap, where only the one propagating mode exists. At the energies outside the gap, backscattering is not suppressed. We discuss the possibility of the effect when the double wire behaves as a ballistic conductor or Anderson insulator depending on whether the Fermi energy lies inside or outside the gap. The localization length is estimated on the basis of the rigorous result for the T matrix of scattering by a single impurity. We show that as a result of the second-order scattering processes, which become dominant in sufficiently strong magnetic fields, the localization length is very sensitive with respect to the parameters of disorder.