Frequency stability of a dual-mode whispering gallery mode optical reference cavity

TL;DR

This paper explores laser frequency stabilization using a dual-mode whispering gallery mode resonator, achieving high stability and low drift through temperature control and theoretical analysis.

Contribution

It demonstrates the effectiveness of a dual-mode temperature stabilization technique in significantly reducing frequency instability in whispering gallery mode resonators.

Findings

Achieved laser frequency stability of 1.3x10^-12 at 1 s

Demonstrated long-term drift of 21 kHz/hr

Reduced effective fractional temperature coefficient to 3.6x10^-8 K^-1

Abstract

We report an investigation of laser frequency stabilization using a whispering gallery mode resonator that is temperature stabilized by a dual-mode technique. This dual-mode technique has yielded mode volume temperature instabilities at the nK level, suggesting that high frequency stability may also be reached. Here, we experimentally and theoretically investigate the dynamics of such a system and the important factors affecting the achievable frequency stability. We calculate that the dual-mode technique can reduce the effective fractional temperature coefficient of the reference system to 3.6x10^-8 K^-1 within the temperature feedback bandwidth. We demonstrate a 1560 nm laser stabilized to 1.3x10^-12 at 1 s and 1.1x10^-10 at 1000 s, corresponding to a long-term drift of 21 kHz/hr.