Study of the refractive index change of Bacteriorhodopsin by the Z-scan and phase-modulated beams techniques

Abstract

Study of intensity dependent refractive index change of polymer film containing bacteriorhodopsin (BR) by the two techniques, Z-scan and phase-modulated beams, and at two excitation wavelengths, 543 and 633 nm, corresponding to the opposite slops of ground-state absorption line of the BR molecule, is reported. A three-level scheme of the BR photocycle is proposed to explain the experimental results.