Vacuum-compatible low-loss Faraday isolator for efficient squeezed-light injection in laser-interferometer-based...

Area of Science:

• Optics and Photonics
• Vacuum Technology
• Thermal Management Systems

Background:

• Faraday isolators are crucial optical components for preventing back-reflections.
• Maintaining high performance of optical devices under high-vacuum and varying temperatures is challenging.
• Existing Faraday isolators often suffer from performance degradation in vacuum or require complex thermal stabilization.

Purpose of the Study:

• To present the first low-loss, vacuum-compatible Faraday isolator with active thermal control.
• To demonstrate high isolation factors and throughput under high-vacuum working conditions.
• To ensure stable and reliable optical isolation performance over extended periods and varying environmental conditions.

Main Methods:

• Development of a novel mechanical and optical configuration for a Faraday isolator.
• Integration of active thermal control to maintain a stable internal temperature.
• Testing and characterization of the device's performance in high-vacuum environments.

Main Results:

• Achieved a throughput as high as 99%.
• Retained an isolation factor higher than 40 dB.
• Demonstrated stable performance over long periods, independent of external temperature variations (within a few Celsius degrees).

Conclusions:

• The developed Faraday isolator is the first to offer low-loss, vacuum compatibility, and active thermal control.
• The device provides excellent optical isolation and high throughput under demanding high-vacuum conditions.
• This technology enables reliable optical system operation in vacuum environments where temperature stability is critical.