||C. Klingshirn, C. Weber, H.-E. Swoboda, R. Renner, F. A.
Majumder, M. Kunz, M. Rinker, H. Schwab and M. Wegener, "Photo-electronic optical
nonlinearities in three - and quasi two - dimensional semiconductors," Proc. SPIE
"Nonlinear Optical Materials," 1017, 32-40, (1988).
We report here on
photo-electronic nonlinearities in direct gap semiconductors, especially those connected
with the transition from a low-density gas of excitons to an electron-hole plasma. We
consider both three-dimensional and quasi two-dimensional semiconductors and compare both
systems. Finally we show that these photo-electronic optical non-linearities can be used
to obtain various types of optical bistability.