Microwave field measurement via Rabi resonances in Cs atoms

Fuyu Sun, Dong Hou, Qingsong Bai +1 more

We have recently presented a technique for measuring unknown microwave (MW) fields based on Rabi resonances induced by the interaction of atoms with a phase-modulated MW field. The single-peak feature of the measurement model makes the technique a valuable tool for simple and fast field measurement. Here we demonstrated a detailed investigation of Rabi resonance of Cs atoms inside a vapour cell. For illustration, we used the Rabi resonance-based field detection technique to determine the field strength inside an X-band cavity for applied power in the range of −21 to 20 dBm. The difference between the practical measurement and the simulation was approximately about 3% for an applied power of 20 dBm, and a higher accuracy could be expected for a larger power input.

金明明 JIN Ming-ming, 张瑞国 ZHANG Rui-guo, 高红卫 GAO Hong-wei +2 more

Fuyu Sun, Dong Hou, Qingsong Bai +3 more

We present a technique for measuring microwave (MW) field based on Rabi resonances induced by the interaction of atoms with a phase-modulated MW field. A theoretical model of field measurement is used to calculate Rabi frequency. Single-peak feature of the measurement model makes the technique a valuable tool for simple and fast field measurement. As an example, we use the technique to determine the MW field strength inside a Cs vapor cell in the X-band rectangular cavity for applied power in the range of -21 dBm to 20 dBm. The results show that this proposed technique is capable for detecting the field over a broad dynamical range.

Haitao Yu, Guilan Li, He Hao +1 more

Fuyu Sun, Jie Ma, Qingsong Bai +3 more

In this letter, an atom-based approach for measuring the microwave (MW) cavity response (including cavity frequency and Q-factor) is presented, which utilizes a MW magnetic field detection technique based on atomic Rabi resonances. We first identify the Rabi resonances on seven π transitions in Cs atoms and demonstrate their uses in continuously frequency-tunable field detectors. With the atom-based field detectors, we then indicate the possibility of reconstructing the MW cavity response by measuring the MW frequency-dependent Rabi frequency (i.e., MW field strength) inside the cavity. To demonstrate this approach, we measured the response curves of a 9.2-GHz cavity and a cavity resonating at 8.3 GHz and 9.7 GHz using π transitions and σ transitions, respectively. We compared the results measured by our approach with those measured by Vector Networker Analyzer and obtained good agreement. From such atom-based, SI-traceable measurements, the MW cavity response can be linked directly to the Rabi frequency, which could be referred to an atomic clock.

Yashika Aneja, Monika Thakran, Asheesh Kumar Sharma +2 more