title: High-contrast, all-optical switching in bacteriorhodopsin films.
abstract: We report experiments with nonlinear-absorption-based, high-contrast, all-optical switching in photochromic bacteriorhodopsin (BR) films. The switching action is accomplished by control of the transmission of a weak probe beam through a BR sample with the help of strong pump beam illumination at 532 nm wavelength. We found that the switching properties of BR films depend on several experimentally controllable parameters such as probe wavelength, pump beam intensity, and excitation rate. A comparative study of the switching behavior and other parameters of practical use was carried out at three probe wavelengths (543, 594, and 633 nm) and various beam powers and pump excitation rates. The results are presented for commercially available wild-type and D96N variant BR films.
authors.affiliation: Optical Science Laboratory, Centre for Research and Education in Science and Technology, Indian Institute of Astrophysics, Bangalore 560034, India.
authors.forename: Ravinder Kumar
authors.initials: RK
authors.lastname: Banyal
authors.forename: B Raghavendra
authors.initials: BR
authors.lastname: Prasad
mesh_terms: D001436:Bacteriorhodopsins / Q000737:chemistry* / Q000528:radiation effects*; D003198:Computer Simulation; D004307:Dose-Response Relationship, Radiation; D008027:Light; D008567:Membranes, Artificial; D008954:Models, Biological; D008956:Models, Chemical; D055095:Optics and Photonics; D018717:Purple Membrane / Q000737:chemistry* / Q000528:radiation effects*; D011829:Radiation Dosage; D012031:Refractometry
chemical_list: D008567:Membranes, Artificial; D001436:Bacteriorhodopsins