Nonlinear polarization drift modeling and real-time compensation in LCVR-based laser power stabilization systems.

Area of Science:

• Physics
• Optical Engineering
• Instrumentation

Background:

• Spin-exchange relaxation-free (SERF) magnetometers require highly stable laser power for reliable operation.
• Liquid crystal variable retarder (LCVR) systems used for power stabilization are susceptible to temperature drift, impacting laser stability.
• Temperature fluctuations induce polarization errors, degrading optical system performance.

Purpose of the Study:

• To investigate and mitigate temperature drift errors in LCVR power stabilization systems for SERF magnetometers.
• To develop and implement a novel compensation model for enhanced long-term laser power stability.
• To improve the performance and reliability of SERF magnetometer and gyroscope systems.

Main Methods:

• An optical transmission model was developed to analyze laser polarization errors due to temperature variations.
• A compensation model incorporating absolute temperature (T) and its time derivative (dT/dt) was implemented.
• The compensation model was deployed on a field-programmable gate array (FPGA) and digital signal processor (DSP) platform.

Main Results:

• The implemented compensation model significantly improved long-term laser power stability.
• Root mean square (RMS) stability improved from 1.4x10^-3 to 5.6x10^-4 over a 24-hour test.
• Allan deviation reached 9.8x10^-6 at 100 seconds, demonstrating enhanced stability.

Conclusions:

• The real-time temperature drift compensation model effectively suppresses polarization-related power fluctuations.
• The proposed method enhances long-term power stability in precision optical systems.
• This approach is crucial for improving the performance of SERF gyroscope systems.