Hiroaki Yamada

Department of Material Science and Technology, Faculty of Engineering, Niigata University, Ikarashi 2-Nocho 8050, Niigata 950-2181, Japan.¹
Tel: +81-25-267-1941; E-mail: [email protected]
¹ Present address: Aoyama 5-7-14-205, Niigata 950-2002, Japan.

Received: 2 July 2003 / Accepted: 20 December 2003 / Published: 21 March 2004

Abstract: We consider quantum diffusion of the initially localized wavepacket in one-dimensional kicked disordered system with classical coherent perturbation. The wavepacket localizes in the unperturbed kicked Anderson model. However, the wavepacket get delocalized even by coupling with monochromatic perturbation. We call the state "dynamically delocalized state". It is numerically shown that the delocalized wavepacket spread obeying diffusion law, and the perturbation strength dependence of the diffusion rate is given. The sensitivity of the delocalized state is also shown by the time-reversal experiment after random change in phase of the wavepacket. Moreover, it is found that the diffusion strongly depend on the initial phase of the perturbation. We discuss a relation between the "classicalization" of the quantum wave packet and the time-dependence of the initial phase dependence. The complex structure of the initial phase dependence is related to the entropy production in the quantum system.

Keywords: localization; delocalization; quantum diffusion; scaling; time irreversibility; phase sensitivity; dissipation.