CAS Key Laboratory of Quantum Information, USTC, Hefei, Anhui 230026, China.
Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
Phys Rev Lett. 2018 Jun 29;120(26):263601. doi: 10.1103/PhysRevLett.120.263601.
The interferometer is one of the most important devices for revealing the nature of light and for precision optical metrology. Although many experiments were performed for probing photon behavior in various configurations, a complete study of photon behavior in a birefringent interferometer has not been performed, to our knowledge. By using an environmental turbulence immune Mach-Zehnder interferometer, we observe tunable photonic beatings by rotating a birefringent crystal versus the temperature of the crystal for both the single photon and two photons. Furthermore, the two-photon interference fringes beat 2 times faster than the single-photon interference fringes. This beating effect is used to determine the thermal dispersion coefficients of the two principal refractive axes with a single measurement: the two-photon interference shows superresolution and high sensitivity. Obvious differences between two-photon and single-photon interference are also revealed in unbalanced situations. In addition, the influence of the photon bandwidth on the beating behaviors that come from polarization-dependent decoherence is also investigated. Our findings will be important for better understanding the behavior of two-photon interference in a birefringent interferometer and for precision optical metrology with quantum enhancement.
干涉仪是揭示光的本质和进行精密光学测量的最重要的设备之一。尽管已经进行了许多实验来探测各种配置下光子的行为，但据我们所知，尚未对双折射干涉仪中的光子行为进行全面研究。通过使用抗环境湍流马赫-曾德尔干涉仪，我们观察到在单光子和双光子两种情况下，通过旋转双折射晶体相对于晶体温度的可调光子拍频。此外，双光子干涉条纹的拍频速度比单光子干涉条纹快 2 倍。这种拍频效应可用于通过单次测量确定两个主折射率轴的热色散系数：双光子干涉具有超分辨率和高灵敏度。在非平衡情况下，还揭示了双光子干涉和单光子干涉之间的明显差异。此外，还研究了光子带宽对偏振相关退相干引起的拍频行为的影响。我们的研究结果对于更好地理解双折射干涉仪中双光子干涉的行为以及利用量子增强进行精密光学测量将非常重要。
