Numéro
Le Journal de Physique IV
Volume 03, Numéro C5, Octobre 1993
Third International Conference on Optics of Excitons in Confined
Page(s) C5-257 - C5-260
DOI http://dx.doi.org/10.1051/jp4:1993550
Third International Conference on Optics of Excitons in Confined

Le Journal de Physique IV 03 (1993) C5-257-C5-260

DOI: 10.1051/jp4:1993550

Exciton saturation and field screening in InGaAs/InGaAsP multiple quantum wells

T. TÜTKEN, B.J. HAWDON, E. SCHEUBLE, M. ZIMMERMANN, P. KÖNIG, A. HANGLEITER, V. HÄRLE and F. SCHOLZ

4. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 7000 Stuttgart 80, Germany


Abstract
We performed differential transmission spectroscopy and time resolved pump probe measurements on biased InGaAs/InGaAsP multiple quantum well structures. At low carrier excitation levels we observe a shift in the energy of the excitonic absorption resonance caused by the photogenerated carriers screening the applied electric field within the quantum wells. Increasing the pump power the exciton transmission energy blue shifts until it reaches the zero internal field energy position. For our pump-probe measurements field screening dominates at pump powers lower than 50 W/cm2 while at higher powers exciton saturation becomes dominant. We deduce a saturation intensity of 250 W/cm2.



© EDP Sciences 1993