München 2004 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

A: Atomphysik

A 15: Poster 2

A 15.33: Poster

Thursday, March 25, 2004, 14:00–16:00, Schellingstr. 3

Non-dispersive Wavepackets in Wannier-Stark Systems — •D. Witthaut, T. Hartmann, S. Mossmann, and H. J. Korsch — Fachbereich Physik, TU Kaiserslautern

We discuss the dispersion of wavepackets in Wannier-Stark systems, consisting of a space-periodic potential and possibly time-dependent fields, both analytically and numerically.

In static 1D systems wavepackets perform a dispersionless periodic motion (Bloch oscillation), while dispersion generally occurs in driven systems. Nevertheless one can construct systems that show a dispersionless motion and even dispersionless transport for certain initial conditions.

In 2D systems the dispersion depends crucially on the direction of the static field with respect to the lattice, being generally much smaller than in field-free systems. We analyze the origin of this small systematic dispersion and its dependence on the field direction.