Theoretical explanation of the absorptive optical bistability in semiconductors due to band-gap shrinkage

Abstract
The creation of an electron-hole plasma in a semiconductor leads to a large band-gap shrinkage which can be used to obtain absorptive optical bistability caused by discontinuous jumps between states of weak band-tail absorption and states of strong band-edge absorption. These effects are described by rate equations for the photons and the free carriers. For CdS the calculated hysteresis phenomena are similar to the experimental results.