Characterization of charge generation and transport in a photorefractive organic glass: comparison between conventional and holographic time-of-flight experiments

Photorefractive organic systems presently show much longer response times t han their inorganic counterparts. The origin of this limitation is not yet fully understood. We present a detailed investigation of the photoelectric processes involved in the photorefractive effect, namely charge generation and charge transport. A comparison between conventional (TOF) and holograph ic time-of-flight (HTOF) experiments, which were used to determine the char ge carrier mobility, is presented. The mobility determined by TOF is shown to depend on the sample thickness. The results show that charge carrier gen eration and transport are not the limiting factors for the cw-response time of holographic experiments on this system. (C) 1999 Elsevier Science B.V. All rights reserved.