Photoelectret characteristics of BaTiO/sub 3/ single crystal

Persistent polarization in single-crystal BaTiO/sub 3/ was induced by the simultaneous application of a DC field and illumination for a known polarizing time. The magnitude of the polarization and its persistence were found to depend on the strength of the poling field, illumination, and duration of polarization. The dark and photopolarization current decay characteristics of the polarized crystal showed that the polarization persisted for a very long time. Photoelectret of BaTiO/sub 3/ crystal was used for two-beam coupling and holographic image recording. Considerable image amplifications were obtained when optimum polarization, beam-mixing geometries, and intensity ratios between the reference and object beams were used.<
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