Time-dependent all-optical logic-gates with bacteriorhodopsin film

In this paper, we proposed time-dependent AND, NOT and A¯B operation based on the relation between input and output intensities of the first-order diffraction beams in degenerate multi-wave coupling. When two coherent green beams are coupled in bacteriorhodopsin (bR) film with a small angle, the intensities of the diffraction beams decrease along with writing time. Based on the phenomenon that the diffraction beams decay along with writing time and the relation between the intensities of input and output beams, we demonstrated the time-dependent optical AND, NOT and A¯B operations.