Role of light fluctuations in the appearance of the bistability of the photocarrier distribution

The effect of light fluctuations on the light-induced bistability of the photocarrier distribution is studied. The bistability can be explained by the threshold character of interband transitions and narrowing of the band gap of the semiconductor with increasing photocarrier density. The stationary probability density of the states and the mathematical expectation of the transition time between states are calculated. It is shown that external noise induces a strongly absorbing state of the semiconductor below the critical intensity of the incident radiation and suppresses stationary states above this value. (C) 1998 American Institute of Physics.