Opt Express. 2023 Mar 13;31(6):10449-10457. doi: 10.1364/OE.485662.
A Rydberg atom-based mixer has opened up a new method to characterize microwave electric fields such as the precise measurement of their phase and strength. This study further demonstrates, theoretically and experimentally, a method to accurately measure the polarization of a microwave electric field based on a Rydberg atom-based mixer. The results show that the amplitude of the beat note changes with the polarization of the microwave electric field in a period of 180 degrees, and in the linear region a polarization resolution better than 0.5 degree can be easily obtained which reaches the best level by a Rydberg atomic sensor. More interestingly, the mixer-based measurements are immune to the polarization of the light field that forms the Rydberg EIT. This method considerably simplifies theoretical analysis and the experimental system required for measuring microwave polarization using Rydberg atoms and is of interest in microwave sensing.
基于里德堡原子的混频器为微波电场的特性描述（如相位和强度的精确测量）开辟了新方法。本研究从理论和实验上进一步证明了一种基于里德堡原子混频器的精确测量微波电场极化的方法。结果表明，拍频信号的幅度随微波电场的极化以 180 度为周期变化，在线性区域内很容易获得优于 0.5 度的极化分辨率，这一水平达到了基于里德堡原子传感器的最佳水平。更有趣的是，基于混频器的测量对形成里德堡电磁感应透明（EIT）的光场的极化不敏感。该方法极大地简化了使用里德堡原子测量微波极化所需的理论分析和实验系统，在微波传感领域具有重要意义。
