All-optical logic gates using bacteriorhodopsin films

We demonstrate all-optical logic gates using bacteriorhodop- sin (bR) film. By studying the transmission of bR film, we advance an all-light-modulated transmission mechanism of bR film: complementary suppression-modulated transmission (CSMT). When a yellow beam (568 nm) and a blue beam (412 nm) illuminate bR film, the two transmitted beams suppress mutually. Based on this mechanism, we design an all- optical operating device in which we implement all 16 kinds of double- variable binary logic operations. The intensity of an incident yellow or blue beam acts as the input to the logic gate and the transmission bears the output of the gate. We can turn this all-optical device into different states using different wavelengths and different intensity illuminations.