Abstract
We present direct experimental evidence that in As/InP quantum wells the band structure undergoes a direct-to-indirect gap transition in k space above a critical value of x. We observe a drastic increase of the measured radiative exciton lifetimes for samples where x>, with depending on well width. using a six-band k⋅p calculation of the valence subbands, we show that for x> the valance-band maximum is at k≠0, i.e., the band structure becomes indirect.
- Received 26 March 1993
DOI:https://doi.org/10.1103/PhysRevB.48.11991
©1993 American Physical Society