PHENOMENOLOGICAL THEORY OF PHOTOCHROMIC MEDIA - OPTICAL-DATA STORAGE AND PROCESSING WITH BACTERIORHODOPSIN FILMS

A phenomenological model for photochromic films incorporating bacterio rhodopsin (BR) molecules is developed. Equations for the propagation o f electromagnetic waves inside a BR film and the temporal evolution of the volume population densities of the molecular states of BR are der ived and subsequently coupled in a self-consistent fashion by means of an expression for the overall susceptibility of the film. Solutions f or the scattered fields in a slab geometry are given in terms of the a ppropriate dyadic Green's functions, and perturbative approximations t hrough the Born and the Rytov methods are discussed. The theory provid es an analytical framework within which various optical data storage a nd processing applications for BR films may be studied. (C) 1997 Optic al Society of America.