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Updated: Oct 3, 2026

Automation of Mode Locking in a Nonlinear Polarization Rotation Fiber Laser through Output Polarization Measurements
Published on: February 28, 2016
Nonlinearity compensation in laser frequency sweep with optical feedback
Abstract:
Frequency-sweep nonlinearity limits the resolution and stability of coherent optical sensing systems. We present a simple optical-feedback-based method that uses the beat signal from a stationary target to characterize the instantaneous sweep rate and iteratively predistort the frequency-tuning waveform, without an auxiliary interferometer or external frequency reference. Experiments with a PZT-tuned 1064 nm frequency-swept microchip laser reduce beat-frequency variance to 0.049 kHz2 (>99% suppression) and compress the overall spectral width by more than 60%, demonstrating effective source-level linearization in both sweep directions.
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