Highly efficient photorefractive polymers for dynamic holography

Abstract

The performance of recently developed highly efficient photoref_ ract1ve polyme_rs .base~ on the photoconducting polymer host poly( N-vinylcarbazole) 1s 1nvest1gated, and the use of these materials as recording media in dynamic holography and other applications is evaluated.- A diffraction efficiency 'rJ = 86% (limited only by absorption and reflection losses), a two-beam coupling net gain coefficient r = 200 cm - 1 and light-induced refractive index modulations as high as lin=7X 10-3 are demonstrated. Hologram growth rates of the order of 500 ms are observed with. recording light intensities <10 mW /cm2 , using either lowpower laser diodes (675 nm) or a HeNe laser (633 nm). The materials show good sensitivity in this part of the spectrum. Applications such as dynamic time-average interferometry are demonstrated.