Abstract Laser power converters (LPCs) based on InxGa1-xAs/GaAs metamorphic heterostructure grown by MOVPE have been investigated. Both direct study of transmission electron microscopy images and analysis of the dark I–V curves at a low photogenerated current have shown the absence of the effect of threading dislocations from the metamorphic buffer on the LPC parameters. It has been shown, according to the “voltage” and “current” invariants that voltage loss in all investigated LPCs evidences the good quality of p-n junctions for the operating mode of high power laser radiation conversion. It has been also demonstrated that the method of saturation current approximation with current invariant allows obtaining the limit voltage losses irrespective of photogenerated current. Band-gap and thickness of the InGaAs LPCs have been adjusted using spectral characteristics. Fundamental losses (thermal and resistive) and ways to minimize them have been discussed. As a result, LPCs based on In0.23Ga0.77As have demonstrated the laser conversion efficiency (λ = 1064 nm) of more than 50% with maintaining the efficiency of more than 48% up to 13 W/cm2.

中文翻译：

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效率超过50%的InGaAs变质激光器(λ=1064 nm)功率转换器的光电参数优化

摘要 研究了基于 MOVPE 生长的 InxGa1-xAs/GaAs 变质异质结构的激光功率转换器 (LPC)。透射电子显微镜图像的直接研究和低光生电流下暗 I-V 曲线的分析都表明，变质缓冲液中的螺纹位错对 LPC 参数没有影响。已经表明，根据“电压”和“电流”不变量，所有研究的 LPC 中的电压损失证明 pn 结在高功率激光辐射转换的工作模式下具有良好的质量。也已经证明，饱和电流近似与电流不变量的方法允许获得极限电压损失，而与光生电流无关。InGaAs LPC 的带隙和厚度已使用光谱特性进行了调整。已经讨论了基本损失（热和电阻）以及将它们最小化的方法。因此，基于 In0.23Ga0.77As 的 LPC 已证明激光转换效率（λ = 1064 nm）超过 50%，并在高达 13 W/cm2 时保持超过 48% 的效率。