Abstract
We compare measured energy shifts of photoluminescence lines in Si/ quantum wells as a function of excitation power with theoretical calculations to conclude that the band alignment of the heterointerface is type II. Experimentally, we study molecular-beam epitaxy-grown fully strained Si/ single quantum wells with Ge fractions from 10% to 36%. These show significant blueshifts of the luminescence at increasing excitation density. Theoretically, we calculate self-consistently transition energy changes taking into account band bending due to the photoinduced charge carriers. Only for type-II band alignment are the experimental and theoretical results compatible.
- Received 11 July 1994
DOI:https://doi.org/10.1103/PhysRevB.50.15191
©1994 American Physical Society