Magnetic-field effects on the transport properties of one-sided rough wires

We present a detailed numerical analysis of the effect of a magnetic field on the transport properties of a ``small-N'' one-sided surface disordered wire. When time-reversal symmetry is broken due to a magnetic field B, we find a strong increase with B not only of the localization length $\ensuremath{\xi}$ but also of the mean free path l caused by boundary states. Despite this, the universal relationship between l and $\ensuremath{\xi}$ does hold. We also analyze the conductance distribution at the metal-insulator crossover, finding very good agreement with random matrix theory with two fluctuating channels within the circular orthogonal (unitary) ensemble in the absence (presence) of B.