Double Rayleigh scattering in a digitally enhanced, all-fiber optical frequency reference

Area of Science:

• Optical Physics
• Metrology
• Fiber Optics

Background:

• Accurate frequency references are crucial for various scientific and technological applications.
• Existing methods often require active stabilization or complex setups.
• Optical fiber-based references offer potential for compact and robust solutions.

Purpose of the Study:

• To demonstrate a passive, all-optical fiber frequency reference.
• To model and understand noise sources limiting the stability of such systems.
• To achieve high frequency stability using a digitally enhanced homodyne interferometer.

Main Methods:

• Utilizing a digitally enhanced homodyne interferometric phase readout.
• Modeling noise contributions from fiber thermal noise.
• Analyzing the coupling of double Rayleigh scattering in the interferometer.

Main Results:

• Achieved a system frequency stability of 0.1 Hz/Hz above 100 Hz.
• Observed that stability is limited by double Rayleigh scattering.
• The achieved stability is approximately five times higher than the thermodynamic noise limit.

Conclusions:

• The passive, all-optical fiber frequency reference demonstrates promising stability.
• Double Rayleigh scattering is a key limiting factor for system performance.
• Further improvements may involve mitigating scattering effects for enhanced frequency precision.