A new scheme of heterodyning facilitated by electro-optic modulator (EOM) is used to characterize the Allan deviation and phase noise of the beat note generated using different pairs of highly coherent lasers. Use of EOM greatly expands optical frequency difference range between the paired lasers suitable for heterodyning. Experimentally demonstrated that sensitivity of optical time-domain reflectometer is mostly determined by the instantaneous linewidth of the probing laser. Observed laser frequency linear drift for all tested lasers was found to be harmless at 1 kHz probing rate. Demonstrated technique can be used to qualify lasers for phase-sensitive optical distributed sensing applications.

中文翻译：

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使用 EOM 促进外差法表征用于相敏相干反射的超窄线宽激光器

一种由电光调制器 (EOM) 促进的外差新方案用于表征使用不同对高度相干激光器产生的拍音的艾伦偏差和相位噪声。EOM的使用极大地扩大了适合外差的成对激光器之间的光频差范围。实验证明，光时域反射仪的灵敏度主要由探测激光的瞬时线宽决定。发现所有测试激光器的观察激光频率线性漂移在 1 kHz 探测速率下是无害的。所展示的技术可用于对激光器进行相敏光学分布式传感应用的鉴定。