Applied Optics
Optical phase conjugation in methylene blue films
A. T. Reghunath, Chinnia Subramanian, P. S. Narayanan, Marokkey R. Sajan
Abstract
Optical phase conjugation in methylene blue sensitized gelatin film has been obtained with 514.5-nm radiation from an argon-ion laser with power levels as low as 50 mW/cm(2) for the pump beam in a degenerate four-wavemixing configuration. The film with a thickness of 110-120 microm prepared from a solution of a 1.8-mmol concentration of methylene blue sensitized gelatin shows a good phase-conjugate reflectivity of 0.5% for this power level at 514.5 nm, which is well away from its absorption peak at ~ 650 nm.