Temperature effects in narrow-linewidth optical cavity control with a surrogate quasi-second-harmonic field

Area of Science:

• Optics and Photonics
• Precision Measurement
• Nonlinear Optics

Background:

• Fabry-Perot cavities are crucial for precision interferometry, typically controlled by direct laser interrogation.
• Certain applications necessitate a surrogate field for effective cavity stabilization.
• Second-harmonic generation (SHG) offers a nonlinear optical method to link a main field to a surrogate field.

Purpose of the Study:

• To investigate the surrogate control approach for Fabry-Perot cavities using a bichromatic cavity.
• To experimentally verify the temperature dependence of a dielectric coating design for surrogate control.
• To develop a comprehensive cavity model for quasi-second-harmonic resonances.

Main Methods:

• Construction of a bichromatic optical cavity.
• Utilizing second-harmonic generation to create a surrogate control field.
• Experimental verification of temperature dependence on differential reflection phase.
• Development of a cavity model incorporating Gouy phase shift and other factors.

Main Results:

• Experimental validation of the temperature dependence for a dielectric coating optimized for surrogate control.
• Demonstration of the bichromatic cavity's utility for surrogate control in optical cavities.
• A comprehensive cavity model for quasi-second-harmonic resonances was developed.

Conclusions:

• The surrogate control approach using a bichromatic cavity is experimentally verified.
• The developed cavity model provides a detailed analysis of the surrogate control method.
• This technique is applicable to precision interferometric systems, including the Any Light Particle Search II experiment.