title: Simple method for determining the gain coefficient of a photorefractive polymer film.
abstract: We propose a simple method for measuring the gain coefficient of two-beam coupling for photorefractive polymer film. To measure the gain coefficient, we attached a phase grating onto the photorefractive polymer film and made an interference pattern between the transmitted and diffracted beams in the photorefractive film by using an illuminating single beam. The gain coefficient values measured at various external fields by our method showed good agreement with those measured by a standard two-beam coupling method. Compared to standard two-beam coupling, this method exhibited fairly improved stability of the output signal to external factors such as human sounds and airstreams.
authors.affiliation: Department of Chemistry, Hanyang University, Seoul 133-791, Korea.
authors.forename: Won-Jae
authors.initials: WJ
authors.lastname: Joo
authors.forename: Nakjoong
authors.initials: N
authors.lastname: Kim