Photocurrent multiplication in organic pigment films

Abstract
Large photocurrent multiplication reaching 10 000 times has been observed in a perylene pigment film sandwiched between Auelectrodes. The phenomenon occurs at the interface between the perylene film and a negatively biased Auelectrode and is found to be associated with electron injection from the Auelectrode to the perylene film through the depletion layer formed in the pigment film under a high electric field, which is built up by the photoaccumulated space charges of trapped holes near the interface.