基于交叉泵浦的受激电磁耦子散射非共线相位匹配方法  

Non-collinear Phase Matching Method of Stimulated Polariton Scattering Based on Cross-pumping

作　　者：张瑞亮 彭苏横 王炳文 耿利杰 翟玉生 张志峰 翟凤潇 杨坤 ZHANG Ruiliang;PENG Suheng;WANG Bingwen;GENG Lijie;ZHAI Yusheng;ZHANG Zhifeng;ZHAI Fengxiao;YANG Kun(School of Physics&Electronic Engineering,Zhengzhou University of Light Industry,Zhengzhou 450000,China;Henan Key Laboratory of Magnetoelectronic Information Functional Materials,Zhengzhou University of Light Industry,Zhengzhou 450000,China)

机构地区：[1]郑州轻工业大学物理与电子工程学院,郑州450000 [2]郑州轻工业大学河南省磁电信息功能材料重点实验室,郑州450000

出　　处：《光子学报》2023年第11期301-310,共10页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.61905223,11904327);河南省科技发展计划(No.222102210319)。

摘　　要：提出一种基于交叉泵浦实现受激电磁耦子散射的非共线相位匹配的方法,获得频率可调谐的窄带Stokes光输出。根据参量放大理论,推导出交叉泵浦受激电磁耦子散射的单程放大增益效率表达式,揭示了交叉泵浦实现受激电磁耦子非共线相位匹配的物理机制。实验上采用泵浦光在晶体侧面全反射的方式构建交叉泵浦,通过旋转晶体改变泵浦光全反射角,实现相位匹配条件的改变和输出Stokes光频率的调谐。输出Stokes光线宽为0.17 nm,波长调谐范围为1068~1076 nm。在15 mJ的泵浦能量下的输出能量为1.07 mJ,能量转化效率为6.8%。本研究为非线性参量转换过程中的相位匹配方法提供一种方案参考,尤其适用于泵浦光脉宽小于纳秒量级的短脉冲情况。Nonlinear optical parametric conversion process based on Stimulated Polariton Scattering(SPS)is an effective way to generate tunable terahertz waves and near-infrared Stokes light with high efficiency.In order to make the SPS process effective,non-collinear phase matching is used to keep the three waves in the crystal at the same phase velocity.Non-collinear phase-matched terahertz wave parametric sources mainly use parametric oscillators and seed-injected parametric generators to achieve frequency limitation and tuning.This paper proposes a new method to achieve non-collinear phase matching of SPS by using two intersecting pump beams to simultaneously excite SPS.The SPS along the transmission direction of the center of the intersection of the pump beams has the same phase matching relationship,and Stokes can obtain the maximum parametric gain and continuous amplification.The SPS in other directions is suppressed by the combined action of a pump beam that satisfies phase matching and a pump beam that does not satisfy phase matching.This method can achieve non-collinear phase matching without relying on a resonant cavity and can be used for short-pulse laser pumping.The basic principle of parametric amplification is studied theoretically,and the gain formula of parametric amplification is derived.Taking cross-pumping based on total reflection of pump light on the side of the crystal as an example,the phase matching relationship of cross-pumping SPS is analyzed,and the phase mismatch of SPS in different transmission directions and the single-pass parametric gain expression of Stokes light are obtained.The gain efficiency curve is obtained through numerical calculation,revealing the physical mechanism of cross-pumping to achieve non-collinear phase matching of SPS.In the experiment,cross-pumping was achieved by grazing incidence of pump light on the side of the crystal at a certain angle to achieve total reflection.By rotating the angle of the crystal,the intersection angle of pump light and phase matching condition

关 键 词：非线性光学 非共线相位匹配 交叉泵浦 受激电磁耦子散射 太赫兹波参量源 

分 类 号：O437.4[机械工程—光学工程]