ELECTROINDUCED AND PHOTOINDUCED EFFECTS IN OPTICAL 2ND-HARMONIC GENERATION AND HYPER-RAYLEIGH SCATTERING FROM THIN-FILMS OF BACTERIORHODOPSIN

The mechanism of optical second-harmonic generation (SHG) in thin soli d oriented and nonoriented films of bacteriorhodopsin (bR) is studied. The role of the random spatial inhomogeneity of the quadratic suscept ibility in the mechanism of diffuse and depolarized SHG in thin solid bR films is discussed. A hyper-Rayleigh scattering formalism is used f or the description of SHG in these films. Electroinduced and photoindu ced effects in SHG are detected, and the saturated concentrations of t he electroinduced and the photoinduced spectral forms of this type of bR film are estimated. Nondestructive SHG readout of bR-based optical memories is suggested. (C) 1997 Optical Society of America.