载流子浓度对光折变LiNbO_3晶体二波耦合增益的影响

THE INFLUENCE OF CARRIER CONCENTRATION ON TWO-WAVE COUPLING GAIN IN PHOTOREFRACTIVE LiNbO3 CRYSTAL

根据光折变微观机制和Ｋｕｋｈｔａｒｅｖ带导模型，分析了ＬｉＮｂＯ３晶体二波耦合系数与载流于浓度的关系．结果表明二波耦合系数随载流于浓度的升高而增大，并逐渐趋于一稳定值．测量了不同Ｃｅ掺杂浓度Ｃｅ：ＬｉＮｂＯ３晶体二波耦合指数增益与载流子浓度的关系，实验结果与理论分析一致．

Based on Kukhtarev's band-conduction model. the relationship between two-wave coupling gain and carrier concentration in photorefractive LiNbO3 crystal is analyzed. The result indicates that the gain increases with the carrier concentration and reaches a saturation value. The exponential gain coefficients of Ce:LiNbO3 crystals with different Ce content have been measured and the experimental results are in good agreement with the theoretical ones.