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Updated: May 9, 2026

Automation of Mode Locking in a Nonlinear Polarization Rotation Fiber Laser through Output Polarization Measurements
Published on: February 28, 2016
A Bell-Bloom experiment with polarization-modulated light of arbitrary duty cycle
I Fescenko1, P Knowles, A Weis
1Physics Department, University of Fribourg, Chemin du Musée 3, 1700 Fribourg, Switzerland. iliafes@gmail.com
Abstract:
We report on a study of polarization-modulation experiments on the 4 → 3 hyperfine component of the D1 transition in Cs vapor contained in a paraffin-coated cell. The laser beam's polarization was switched between left- and right-circular polarization at a rate of 200 Hz. Variations of the transmitted light power were recorded while varying the amplitude of a transverse magnetic field. The power shows electromagnetically induced transparency (EIT) resonances when the atomic Larmor frequency matches a harmonic of the modulation frequency. We made a quantitative study of the resonance amplitudes with square-wave modulations of various duty cycles, and find an excellent agreement with recent algebraic model predictions.

