Compensation method for temperature-induced phase mismatch during frequency conversion in high-power laser systems
Compensation method for temperature-induced phase mismatch during frequency conversion in high-power laser systems
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DOI：
10.1364/josab.33.000525
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发表时间：
2016-04
影响因子：
1.9
通讯作者：
Zijian Cui;De’an Liu;Meizhi Sun;Jie Miao;Jianqiang Zhu
中科院分区：
文献类型：
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作者：
Zijian Cui;De’an Liu;Meizhi Sun;Jie Miao;Jianqiang Zhu
提出了一种对变频过程中温度变化引起的相位失配进行补偿的方法，并建立了理论模型。该方法基于由两个非线性晶体和一个电光晶体组成的补偿方案，通过电光效应来补偿相位失配，并通过改变电压来实现新的尺寸调整。在原理验证研究中，给出了级联KH_2PO_4(KDP)和KD_2PO_4(DKDP)晶体分别从1053 nm转换到526.5 nm和351 nm的例子。三维数值模拟表明，倍频和倍频的转换效率随温度的变化而变化。结果表明，倍频和倍频的温度接受带宽分别是传统单晶方法的2.4倍和3.4倍。在24℃~26℃的温度范围内，对192束光束的转换效率进行了稳定性分析，倍频和三倍频转换效率的标准偏差分别从1.25%和6.61%降低到0.18%和0.56%。此外，还分析了反射损耗对输出效率的影响，结果表明反射损耗对输出效率的影响很小。这表明该方法在降低转换效率的温度敏感性方面可能是有效的。
A compensation method for phase mismatch caused by temperature variation during the frequency conversion process is proposed and the theoretical model is established. The method is based on the principle that phase mismatch can be compensated via the electro-optic effect based on a compensation scheme consisting of two nonlinear crystals and an electro-optic crystal; further, a new dimension adjustment can be achieved by changing the voltage. In a proof-of-principle study, frequency conversion from 1053 nm to 526.5 nm and 351 nm by cascade KH2PO4 (KDP) and KD2PO4 (DKDP) crystals, respectively, is presented as an example. Three-dimensional numerical simulations are conducted to show that the conversion efficiency of frequency doubling and tripling varies with temperature. The results show that the temperature acceptance bandwidth of doubling and tripling can be 2.4 and 3.4 times larger, respectively, than that of the traditional method using a single crystal. We also analyze the stability of the conversion efficiency for 192 beams by our proposed method when the temperature is randomly varied within the range of 24°C–26°C. The standard deviation of the conversion efficiency of frequency doubling and tripling decreases from 1.25% and 6.61% to 0.18% and 0.56%, respectively. In addition, the influence of the reflection loss on the output efficiencies is also analyzed and the results show that it is very small. This indicates that this method may be effective in reducing the temperature sensitivity of conversion efficiency.