Brillouin Backaction Thermometry for Modal Temperature Control

TL;DR

This paper introduces a novel Brillouin backaction thermometry technique that enables precise modal temperature control in microresonator lasers, enhancing frequency stability for applications like atomic clocks and gyroscopes.

Contribution

It presents a new method to measure and lock the modal temperature using Brillouin backaction, applicable across various Brillouin laser platforms.

Findings

Demonstrated phase-sensitive temperature locking in a chip-based Brillouin laser.

Achieved precise temperature control by adjusting resonator free spectral range.

Showed potential for improved frequency stability in metrology applications.

Abstract

Stimulated Brillouin scattering provides optical gain for efficient and narrow-linewidth lasers in high-Q microresonator systems. However, the thermal dependence of the Brillouin process, as well as the microresonator, impose strict temperature control requirements for long-term frequency-stable operation. Here, we study Brillouin back action and use it to both measure and phase-sensitively lock modal temperature to a reference temperature defined by the Brillouin phase-matching condition. At a specific lasing wavelength, the reference temperature can be precisely set by adjusting resonator free spectral range. This backaction control method is demonstrated in a chip-based Brillouin laser, but can be applied in all Brillouin laser platforms. It offers a new approach for frequency-stable operation of Brillouin lasers in atomic clock, frequency metrology, and gyroscope applications.