Stabilizing Fabry-Perot optical frequency comb with differential phase detection and bias compensation

Area of Science:

• Physics
• Optical Engineering
• Metrology

Background:

• Optical frequency combs (OFCs) are crucial for high-precision measurements.
• Environmental factors can destabilize OFCs, limiting their long-term performance.
• Existing stabilization methods often require complex setups or external reference signals.

Purpose of the Study:

• To present a novel stabilization technique for optical frequency combs.
• To demonstrate long-term stability of an OFC against environmental variations.
• To validate the effectiveness of a homodyne phase-locked loop for OFC stabilization.

Main Methods:

• Utilized a Fabry-Perot phase modulator for OFC generation.
• Measured relative phase changes of upper and lower sideband beat signals to detect variations.
• Employed a homodyne phase-locked loop to control OFC bias voltage for compensation.

Main Results:

• Achieved a relative phase change of only 0.056° over 3800 seconds.
• Demonstrated stable OFC performance even under drastic temperature changes.
• Differential phase detection effectively eliminated common-mode noise.

Conclusions:

• The proposed stabilization method ensures long-term OFC stability without external references.
• The technique is robust against environmental disturbances like temperature fluctuations.
• This advancement enables more reliable and precise optical frequency comb applications.