【摘要】 带输运模型是目前被广泛接受的光折变理论.该模型以扩散机制为主.在某些情况下加上两个修正,即有外场时的漂移机制和光生伏打效应.其中光生伏打效应被考虑为等效于外加电场.而且常常被忽略了.作者认为光生伏打效应应当总被看作与扩散相并列的光折变机制,而且在铁电晶体.如LiNbO₃.中.光生伏打效应常常超过扩散而成为光折变过程的主要机制.文中将已有的光生伏打效应的唯像理论加以扩展,对产生光折变光栅的过程给出了较全面的分析.更多还原

【Abstract】 The band transport model is now a widely accepted photorefractive theory. In this model, diffusion mechanism acts as a main role and in some cases two modifications, i. e. , drift under an applied field and the photovoltaic effect, are added. Actually, the photovoltaic effect should aloways be considered as important as the diffusion, and in the case of fcrroelectrics, e. g. , LiNbO3, this effect often dominates over the latter and thus becomes the main photorefractive mechanism. In this paper,.the phenomcnological theory of photovoltaic effect was developed and an all-around analysis for the formation of the photorefractive grating is given.更多还原