Li Yuanyuan, Chu Weidong, Yang Ning, Ge Lei, Xie Yan, Zhang Wei, Duan Suqing, Wang Yingxin, Sun Jialin
Opt Express. 2019 Sep 16;27(19):27076-27087. doi: 10.1364/OE.27.027076.
Self-mixing velocity sensor based on a mutual-injected two-element terahertz quantum cascade laser (THz QCL) array is studied theoretically. The working characteristics of mutual-injected THz QCL array with different frequency detunings and self-mixing feedback strengths, as well as their influences on the self-mixing measurements are discussed in detail. Within the phase-locked range, each laser in the array reaches a stable state rapidly and can be used as a self-mixing detector due to the mutual injection coupling. The array will no longer be phase-locked when the frequency detuning of the lasers is too large, and only the laser that receives the feedback light can still be used for self-mixing velocity measurements. It is also found that even for the case of strong feedback, the THz QCLs will not be completely unstable and the self-mixing velocity measurements could also be possible. In addition, the simulation also shows that the array could measure two independent moving targets simultaneously. These results provide the theoretical support for the future applications of THz QCL arrays in self-mixing sensors.
对基于互注入双元太赫兹量子级联激光器（THz QCL）阵列的自混合速度传感器进行了理论研究。详细讨论了具有不同频率失谐和自混合反馈强度的互注入THz QCL阵列的工作特性，以及它们对自混合测量的影响。在锁相范围内，阵列中的每个激光器由于互注入耦合而迅速达到稳定状态，并可作为自混合探测器使用。当激光器的频率失谐过大时，阵列将不再锁相，只有接收反馈光的激光器仍可用于自混合速度测量。还发现，即使在强反馈情况下，THz QCL也不会完全不稳定，自混合速度测量也是可行的。此外，模拟还表明该阵列可以同时测量两个独立的移动目标。这些结果为THz QCL阵列在自混合传感器中的未来应用提供了理论支持。
