Measuring magnetic field inside a microwave cavity via Rabi resonances in Cs atoms

TL;DR

This paper introduces a rapid and straightforward method for measuring microwave magnetic fields inside a cavity using Rabi resonances in cesium atoms, demonstrating broad dynamic range detection.

Contribution

It presents a novel technique leveraging Rabi resonances for microwave field measurement, with a theoretical model and experimental validation inside a Cs vapor cell.

Findings

Effective measurement of MW field strength over a broad range.

Single-peak feature simplifies the measurement process.

Validated technique within X-band cavity for -21 dBm to 20 dBm power.

Abstract

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.