Abstract
Wannier-Stark ladder transitions in the photocurrent spectra of (111)B As-GaAs strained-layer piezoelectric superlattices are reported. Both vertical transitions in the same well and diagonal transitions between adjacent wells are observed. In contrast to (100) superlattices, the Wannier-Stark spectra are observed for both senses of applied bias relative to zero potential drop across the superlattice. The observed transition energies are found to be in good agreement with the predictions of exciton calculations. The piezoelectric field is deduced in a simple and direct way from analysis of the spectra as a function of bias.
- Received 23 August 1995
DOI:https://doi.org/10.1103/PhysRevB.52.R14340
©1995 American Physical Society