Mirror Coating Thermal Noise Mitigation Using Multi-Spatial Mode Cavity Readout

Abstract

We present an approach to mitigate coating thermal noise in optical cavities by using multiple TEM spatial modes to readout and stabilize laser frequency. With optimal weightings we synthesize a wider sampling of the mirror surface, improving averaging of Brownian thermal fluctuation. We show thermal noise improvement factors of 1.57, comparable to a MESA beam of a nominal 12 m prototype cavity, and a factor 1.61 improvement over the ${\text{TEM}}_{00}$ using three modes in a 0.1 m cavity for a practical laboratory experiment: equivalent to cooling mirrors to 120 K from room temperature.

9 pages, 5 figure. Target: PRA

References in corpus (6)

• LIGO: The Laser Interferometer Gravitational-Wave Observatory
• Compact, thermal-noise-limited optical cavity for diode laser stabilization at 1 x 10-15
• On orbit performance of the GRACE Follow-On Laser Ranging Interferometer
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