Optical memory effect of bacteriorhodopsin under an electric field

Optically induced absorption changes in bacteriorhodopsin under an electric field are investigated. A new intermediate appears due to light illumination under an electric field at room temperature. This optically induced state remains stable until it is again illuminated. The application of an electric field appears to change the energy level of bacteriorhodopsin molecules. Results show that an optical-writing, optical-erasing memory using bacteriorhodopsin which can function at room temperature can be fabricated.