Wave packet dynamics in a semiconductor superlattice

We examine the time development of a wave packet in a superlattice miniband in a constant electric field, explicitly determining the time dependence o f the probability density. Our analytic results permit the identification o f breathing motion of the wave packet as well as Bloch oscillatory motion o f its center-of-mass. The dynamical development of a Gaussian wave packet i s exhibited, showing the appearance of images of the initial wave packet in nearby superlattice cells, exemplifying their participation in Bloch oscil latory and breathing motions. (C) 2001 Elsevier Science B.V. All rights res erved.