Optical Bistability and the Optical Transistor Using Semiconductors

摘要: Optical bistability (OB) is, as its name implies, the existence of two stable states for one set optical input conditions. The concept has been in some twelve years since suggestion Szoke et al1, but was first demonstrated by Gibbs al.2 using Na vapour active medium inside a Fabry-Perot cavity. type OB to be proposed so-called “absorptive” which saturable absorber is placed cavity tuned on-resonance, idea being that field increased, would “bleach”, thus further increasing finesse (or “Q-factor”). Ideally this process self- sustaining leading “switching-on” action at intensity with “switching-off” only occurring lower intensities, creating bistable region between switch-on and switch-off intensities. However, turns out difficult achieve because requirement on degree bleaching rather severe (ie. ratio 8 low high absorption limits).