Dynamic holographic liquid crystal device containing nanoscale CuPc film

Fengfeng Yaoa, Rongqu Honga, Yunpen Gaoa, Zhaoheng Wanga, Yanbo Pei*abc, Chunfeng Houabc, Yongyuan Jiangabcd & Xiudong Sunabcda Department of Physics, Institute of Modern Optics, Harbin Institute of Technology, Harbin, Chinab Key Laboratory of Micro-Nano Optoelectronic Information System of Ministry of Industry and Information Technology, Harbin, Chinac Key Laboratory of Micro-Optics and Photonic Technology of Heilongjiang Province, Harbin Institute of Technology, Harbin, Chinad Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, ChinaCONTACT Yanbo Pei peiyanbo@hit.edu.cnABSTRACTIn this paper, CuPc-film-containing nematic liquid crystal (NLC) cells were fabricated, and dynamic holographic gratings recorded in the NLC cells were studied. The dependence of the diffraction efficiency on the applied voltage, light intensity, and the thicknesses of CuPc and NLC film was investigated. The high diffraction efficiency about 30% and the moderate build-up and erasing time in the order of magnitude of 0.1 s were achieved. The asymmetric energy transferring in two-beam coupling indicates photorefractive (PR) nature of the grating. The results of the photoinduced change of birefringence experiments suggest that the surface charge at the interface between the CuPc film and the NLC film plays a crucial role in the PR effect and the CuPc–NLC interface is mainly responsible for the formation of modulated surface charge layer and enables the photoelectric function of the NLC device. Our research may provide a new material option to optimise and develop NLC device for optical information processing and storage.Graphical Abstract