基于保偏布喇格光栅的窄线宽半导体激光器

Narrow linewidth semiconductor laser based on polarization maintaining Bragg grating

为了研制面向量子精密测量应用的近红外波段光纤光栅外腔半导体激光器,采用独立设计的高偏振依赖增益芯片和双折射光纤布喇格光栅,通过法布里-珀罗等效谐振腔模型,系统分析了光栅反射率、外腔和芯片长度对激光线宽的影响。结果表明,所研制激光器实现了54.46 mW的输出功率、58.88 dB的边模抑制比和24.46 dB的偏振消光比,利用延迟自外差拍频方法测得的洛伦兹线宽低至2.69 kHz。此研究为独立设计制备分立器件的单频窄线宽外腔半导体激光器提供参考,有望应用于雷达成像、陀螺仪、磁力仪和原子钟等量子精密测量领域。

In order to develop a near-infrared band fiber grating external cavity semiconductor laser for quantum precision measurement applications,a high polarization dependent gain chip and a birefringent fiber Bragg grating were designed independently,the effects of grating reflectivity,external cavity,and chip length on laser linewidth were systematically analyzed based on the Fabry-Pérot equivalent resonant cavity model.The results showe that the developed laser achieves an output power of 54.46 mW,a side mode suppression ratio of 58.88 dB,and a polarization extinction ratio of 24.46 dB.The Lorentz linewidth measured is 2.69 kHz by delayed self-heterodyne beat frequency method.This study provides a reference for the single frequency narrow linewidth external cavity semiconductor lasers with independent design and preparation of discrete devices,and is expected to be used in quantum precision measurement fields such as radar imaging,gyroscopes,magnetometers,and atomic clocks.