Indirect excitons in strained GaxIn1-xAs/InP quantum wells

P. MICHLER; A. HANGLEITER; A. MORITZ; G. FUCHS; V. HÄRLE; F. SCHOLZ

doi:doi:10.1051/jp4:1993553

Numéro		Le Journal de Physique IV Volume 03, Numéro C5, Octobre 1993 Third International Conference on Optics of Excitons in Confined


Page(s)		C5-269 - C5-272
DOI		https://doi.org/10.1051/jp4:1993553

Third International Conference on Optics of Excitons in Confined

Le Journal de Physique IV 03 (1993) C5-269-C5-272
DOI: 10.1051/jp4:1993553

Indirect excitons in strained Ga_xIn_1-xAs/InP quantum wells

P. MICHLER, A. HANGLEITER, A. MORITZ, G. FUCHS, V. HÄRLE and F. SCHOLZ

4. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany

Abstract
We present direct experimental evidence that in Ga_xIn_1-xAs/InP quantum wells the bandstructure undergoes a direct-to-indirect gap transition in k-space above a critical value of x. We observe a drastical increase of the measured radiative exciton lifetimes for samples where x>x_c, with x_c, depending on well width. Using a six-band k.p calculation of the valence subbands we show that for x>x_c the valence band maximum is at k ≠ 0, i.e. the bandstructure becomes indirect.