Abstract

There was a longstanding theoretical debate whether Bloch-oscillations or their energy-domain equivalent, Wannier-Stark-states, exist or whether they are suppressed by Zener-tunneling to higher bands. Both phenomena have recently been observed in many experiments in semiconductor heterostructures where coherence of the electronic ensemble was preserved longer than the Bloch-oscillation period. Surprisingly, the effect of Zener tunneling was never observed or discussed in these publications.

© 2001 Optical Society of America