With submicrometer thick photoconducting, semiconductor ZnSe thin films as interlayers between ITO glass and thin film of C60 doped mixture of polymer poly[N-vinylcarbazole] (PVK) and nematic liquid crystal (LC) 4,4’-npentylcyanobiphenyl (5CB), an updatable holographic recording medium was fabricated. When two laser beams were overlapped in the holographic recording medium, 2D diffraction patterns were seen, along with several interesting observations. The frequent sign changing of energy transferring between the two transmitted laser beams and large dynamic change in different diffraction orders implied complex processes of electric charge generation, transportation and compensation in the interfaces and within composite polymer film. Electrostatic modification based surface grating formation was proposed to explain all the findings.
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