Dynamic continuous-wave spectroscopy of coherent population trapping at phase-jump modulation

TL;DR

This paper introduces a phase-jump modulation technique for dynamic continuous-wave spectroscopy of CPT resonances, improving frequency stabilization and reducing sensitivity to lineshape asymmetry, with potential applications in atomic clocks.

Contribution

The paper develops a novel phase-jump modulation method for CPT spectroscopy, providing a new approach for frequency stabilization with reduced lineshape sensitivity.

Findings

Experimental results agree with theoretical models

Reduced sensitivity to lineshape asymmetry demonstrated

Potential for improved atomic clock stability

Abstract

A method of dynamic continuous-wave spectroscopy of coherent population trapping (CPT) resonances using phase modulation of the jump type is developed. The time evolution of the spectroscopic signal is investigated. A method for the formation of an error signal for frequency stabilization is proposed. We show that our approach has a reduced sensitivity to the lineshape asymmetry of the CPT resonance. The experimental results are in good qualitative agreement with theoretical predictions based on a mathematical model of a three-level $\Lambda$ system in a bichromatic field. This method can be used in atomic frequency standards (including chip-scale atomic clocks).