Spreading and localization of wavepackets in disordered wires in a magnetic field - art. no. 081306

We study the localization properties of wavepackets in disordered wires in a magnetic field. A formula for the steady-state wave function at the cross over regime from preserved to broken time-reversal symmetry is proposed, wh ich is in excellent agreement with our numerical data. In contrast to a rec ent supersymmetry approach the extracted asymptotic decay rate of the stead y state changes smoothly in the crossover regime. Finally, we investigate f luctuation properties around the steady state and find a scaling for the va riance of the wavepacket which also shows a smooth transition due to the ma gnetic field.