Time distribution of the domain-boundary relocation in superlattices

Static domain formation in doped, weakly coupled semiconductor superlattices results in several current branches separated by discontinuities that exhibit hysteresis. The transition from one branch to its adjacent higher and lower one is studied by time-resolved switching experiments. The distribution function of the relocation time for up and down jumps changes from a simple Gaussian to a first-passage time (FPT) form, when the final voltage on the adjacent branch approaches a discontinuity in the current-voltage characteristic. This observation indicates that for a smaller voltage distance from the discontinuity (FPT distribution) the system reaches the final state via an unstable intermediate state. In contrast, for a larger voltage distance from the discontinuity (Gaussian distribution), the system arrives directly at the final state, because the intermediate state does not exist. © 2002 Elsevier Science B.V. All rights reserved.

Duke Scholars

Author Stephen W. Teitsworth Physics