A scheme for measurement of microwave (MW) electric field is proposed via multi-photon coherence in Rydberg atoms. It is based on the three-photon electromagnetically induced absorption (TPEIA) spectrum. In this process, the multi-photon produces a narrow absorption peak, which has a larger magnitude than the electromagnetically induced transparency (EIT) peak under the same conditions. The TPEIA peak is sensitive to MW fields, and can be used to measure MW electric field strength. It is interesting to find that the magnitude of TPEIA peaks shows a linear relationship with the MW field strength. The simulation results show that the minimum detectable strength of the MW fields is about 1/10 that based on an common EIT effect, and the probe sensitivity is improved by about 4 times. Furthermore, the MW sensing based on three-photon coherence shows a broad tunability, and the scheme may be useful for designing novel MW sensing devices.
Fisher-Based Sensitivity Framework for Rydberg Atom Microwave Electrometry
College of Metrology Measurement and Instrument, China Jiliang University（中国计量大学计量测试与仪器学院）；Department of Physics, Westlake University（西湖大学物理系）；Qianyuan Laboratory, Xihu District, Hangzhou, Zhejiang Province（钱源实验室）
Floquet-sideband-enhanced shortwave electrometry with Rydberg atoms
Xi’an Jiaotong University（西安交通大学）；Nanjing University（南京大学）；Beijing Institute of Radio Metrology and Measurement（北京无线电计量测试研究所）；East China Normal University（华东师范大学）；Hefei National Laboratory（合肥国家实验室）；University of Arkansas（阿肯色大学）
Reactive near-field subwavelength microwave imaging with a non-invasive Rydberg probe
State Key Laboratory of Quantum Optics Technologies and Devices, Institute of Laser Spectroscopy（量子光学技术与器件国家重点实验室激光光谱研究所）；Collaborative Innovation Center of Extreme Optics, Shanxi University（极端光学协同创新中心山西大学）
Microwave-field quantum metrology with inherent robustness against detection losses enabled by Rydberg interactions
Centre for Quantum Optical Technologies, Centre of New Technologies, University of Warsaw（华沙大学新技术中心量子光学技术研究中心）；Faculty of Physics, University of Warsaw（华沙大学物理学院）
