Three types of electronic optical bistabilities in CdS

Abstract

The authors investigate optical bistability in CdS, induced by photo-electronic non-linearities. Varying the photon energy and the temperature of the sample they find three different types of optical bistability. The switching times are always around 1 ns or below, notably 300 ps for dispersive optical bistability. Optical bistability by bleaching of absorption at room temperature shows a contrast ratio of about 50 between the two stable branches. The dependence on various parameters, including the microscopic foundations, is discussed experimentally as well as theoretically.