Octave Spanning Visible to SWIR Integrated Coil-Stabilized Brillouin Lasers

TL;DR

This paper presents a novel integrated coil-stabilized Brillouin laser architecture that operates over an octave span from visible to SWIR wavelengths, achieving ultra-low linewidths and high stability suitable for precision applications.

Contribution

The work introduces a wavelength-flexible, integrated Brillouin laser design with two-stage noise reduction on a silicon nitride platform, covering a broader spectrum with record low linewidths and stability.

Findings

Achieved linewidths as low as 1 Hz to 17 Hz across wavelengths

Demonstrated frequency noise reduction over 1 Hz to 10 MHz

Achieved high stability with Allan deviations down to 6.5 x 10^-13

Abstract

Narrow linewidth stabilized lasers are central to precision applications that operate across the visible to short-wave infrared wavelengths, including optical clocks, quantum sensing and computing, ultra-low noise microwave generation, and fiber sensing. Today, these spectrally pure sources are realized using multiple external cavity tabletop lasers locked to bulk-optic free-space reference cavities. Integration of this technology will enable portable precision applications with improved reliability and robustness. Here, we report wavelength-flexible design and operation, over more than an octave span, of an integrated coil-resonator-stabilized Brillouin laser architecture. Leveraging a versatile two-stage noise reduction approach, we achieve low linewidths and high stability with chip-scale laser designs based on the ultra-low-loss, CMOS-compatible silicon nitride platform. We report operation at 674 and 698 nm for applications to strontium neutral and trapped-ion clocks, quantum sensing and computing, and at 1550 nm for applications to fiber sensing and ultra-low phase noise microwave generation. Over this range we demonstrate frequency noise reduction from 1 Hz to 10 MHz resulting in 1.0 Hz -17 Hz fundamental and 181 Hz - 630 Hz integral linewidths and an Allan deviation of 6.5 x 10-13 at 1 ms for 674 nm, 6.0 x 10-13 at 15 ms for 698 nm, and 2.6 x10-13 at 15 ms for 1550 nm. This represents the lowest achieved linewidths and highest stability for integrated stabilized Brillouin lasers over an order of magnitude improvement in operating wavelength range. These results unlock the potential of integrated, ultra-low-phase-noise stabilized lasers for precision applications and further integration in systems-on-chip solutions.