We report the effective nonlinearity for photochromic conversion in a blue-membrane bacteriorhodopsin film hosted in a dry polyvinyl alcohol matrix. The shift in absorption maximum on photoconversion in this film is larger than that of the same material in hydrated form, thus offering a larger modulation of the refractive index. The photoexcited index modulation is stable for several months, which provides for holographic data recording and long-term photochromic data storage. The effective index modulation is experimentally measured and is in good agreement with the theoretical predictions based on the Kramers–Kronig transformation.
© 1996 Optical Society of America
Jack Tallent, Q. Wang Song, Zengfa Li, Jeff Stuart, and R. R. Birge, "Effective photochromic nonlinearity of dried blue-membrane bacteriorhodopsin films," Opt. Lett. 21, 1339-1341 (1996)