Robust frequency stabilization and linewidth narrowing of a laser with large intermittent frequency jumps using an optical cavity and an atomic beam

TL;DR

This paper presents a robust method for stabilizing laser frequency and narrowing linewidth despite large intermittent jumps, using an atomic beam and a high-finesse cavity, enhancing stability and simplicity.

Contribution

It introduces a novel stabilization technique combining cavity locking with atomic fluorescence feedback, improving robustness against frequency jumps and simplifying the setup.

Findings

Laser maintained stability for over a week

Achieved narrow linewidth at 556 nm

Enhanced accuracy for Yb optical lattice clock

Abstract

An experimental method is developed for the robust frequency stabilization using a high-finesse cavity when the laser exhibits large intermittent frequency jumps. This is accomplished by applying an additional slow feedback signal from Doppler-free fluorescence spectroscopy in an atomic beam with increased frequency locking range. As a result, a stable and narrow-linewidth 556 nm laser maintains the frequency lock status for more than a week, and contributes to more accurate evaluation of the Yb optical lattice clock. In addition, the reference optical cavity is supported at vibration-insensitive points without any vibration isolation table, making the laser setup more simple and compact.