Recently-developed photorefractive polymer composites now show sufficiently high performance to allow effects such as self-pumped phase conjugation and speeds approaching video frame rates. To understand the mechanisms leading to this new level of performance, a simple spectroscopic method for the determination of the trap density in fullerene-sensitized photorefractive (PR) polymers is presented. This method is compared with results obtained from traditional trap density measurements which involve two-wave mixing, and good correlation is observed. This technique is used to identify the inactive (compensating) trap as the nonlinear optical chromophore (NLO).
© 1999 Optical Society of AmericaPDF Article