Reversible photobleaching of bacteriorhodopsin molecules exposed to 570 mn laser light

Abstract

The phenomenon of reversible photobleaching in bacteriorhodopsin (BR) molecules exposed to 570 nm laser is presented. Creation of non-absorbing molecules in the bleached state is analysed theoretically using a simple theoretical model based on the excited-state absorption process. The analysis helps in ascertaining the percentage of molecules in the bleached state in the BR-based memory devices at any given time. The theory provides a bleaching parameter quantifying the number of photons the BR molecules can absorb before they reach a bleached state