传统激光雷达探测灵敏度不断提高，但仍然受激光光源的量子噪声以及探测端引入的额外噪声等因素限制。为了进一步提高激光雷达的探测性能，提出利用量子压缩态光场作为激光雷达的本振信号提高激光雷达探测精度的新方案，分析了所提出方案提高激光雷达探测精度的关键因素。制备了集成化低噪声压缩态光场并进行了激光雷达多普勒信息测量实验。实验结果表明，相较于传统相干多普勒激光雷达探测方案，所提方案实现了多普勒信息探测灵敏度3 dB的提升，为量子激光雷达中多普勒信息等微弱信号的探测提供研究途径。

Our previous work had proved pump field noise coupling in the seed field injected optical parametric amplifier (OPA) at a certain analysis frequency. Inspired by this noise coupling mechanism, the frequency dependent squeezing factor due to excess pump noise was experimentally demonstrated. Apart from a reduced squeezing level with an increased noise, the results also prove that a broadband squeezing noise spectrum is not frequency dependent on the amplitude modulated pump field, but limited by the bandwidth of the amplitude modulator and OPA resonator, and the effective measurement is carried out in the frequency range of 2–10 MHz. It provides a guidance to design a broader-bandwidth, higher-level bright squeezed light.

激光精密测量的测量精度主要受限于光场噪声和各种技术噪声，在去耦合技术噪声后，光场量子噪声成为限制其测量精度的主要因素。文中针对全固态单频激光器强度噪声特性，阐述强度噪声的主要来源及其对功率噪声谱的影响，回顾了传统直流反馈控制、光学交流耦合反馈控制和量子压缩器三种强度噪声抑制技术。通过回顾相关技术的发展历程，总结了强度噪声抑制技术的当前发展水平和未来发展趋势——三种技术相结合的抑噪方案是解决高灵敏度探测的重要途径。

Squeezed states belong to the most prominent non-classical resources. They have compelling applications in precise measurement, quantum computation, and detection. Here, we report on the direct measurement of 13.8 dB squeezed vacuum states by improving the interference efficiency and gain of balanced homodyne detection. By employing an auxiliary laser beam, the homodyne visibility is increased to 99.8%. The equivalent loss of the electronic noise is reduced to 0.05% by integrating a junction field-effect transistor (JFET) buffering input and another JFET bootstrap structure in the balanced homodyne detector.