A theoretical study of transient effects in absorptive optical bistability

Vincenzo Gino Benza, L. A. Lugiato

James D. Farina, Lorenzo M. Narducci, J. M. Yuan +1 more

James D. Farina, Lorenzo M. Narducci, Jun‐Hui Yuan +1 more

Hui Wang, Lan Wen-guang, Lin Wei-Zhu +2 more

Based on the established theory of photoinduced exciton bleaching of the polymers with nondegenerated ground state,we calculated the transient mirrorless optical bistability of photoexcitation and relaxation processes in the polymers.The results show that the transient saturation absorption mirrorless optical bistabilities and the increasing absorption mirrorless optical bistabilities can be obtained from the ultrafast excitation and relaxation processes in the polymers with nondegenerate ground state,and the switching time of the optical bistabilities is of the order of fs or ps.With the increase of the delay time of the probe pulse relative to pump pulse,the nature of mirrorless optical bistability can change from the saturation absorption optical bistability to increasing absorption optical bistability,and the rate of change is proportional to the speed of relaxation of the photoinduced exciton.

Luigi Lugiato

Optical bistability is a phenomenon that arises in the transmission of light by an optical cavity filled with a medium which presents saturable absorption or nonlinear dispersion. From the theoretical viewpoint, optical bistability is a remarkable example of cooperative behaviour in an open system driven far from thermal equilibrium. From the practical viewpoint, optical bistability offers the possibility of realizing memory elements that may perhaps be used to construct an optical computer. We illustrate the basic physical principles of optical bistability at steady state, and the main features of the transient behaviour. The role and the effects of fluctuations (noise) are described in general. Particular attention is devoted to the situations in which the output of the system is not stationary in time, but oscillatory (self-pulsing behaviour), so that the system works as a converter of continuous wave light into pulsed. It is shown that, according to the values of the external parameters, the oscillations can be either periodic in time or completely aperiodic (optical turbulence). The state of the art in the problem of optical bistability is briefly discussed.

R. Deserno, Rolf Kumme, Fedor M. Mitschke +2 more

The effect of external noise of different spectral distributions on the dynamic behaviour of an intrinsic optical bistable device is studied. Our experiments are performed under absorptive conditions in a sodium-filled nonlinear Fabry-Perot in the bad cavity limit. Alternatively, a bistable electronic circuit (Schmitt trigger) is shown to exhibit the same type of noise phenomena while admitting more detailed investigations.