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arXiv · 1909.11249

Mode-locked and tunable fiber laser at the 3.5 $μ$m band using frequency-shifted feedback

Ori Henderson-Sapir·Nathaniel Bawden·Matthew R. Majewski·Robert I. Woodward·David J. Ottaway·Stuart D. Jackson3
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Abstract

We report on a mid-infrared mode-locked fiber laser that uses an acousto-optic tunable filter to achieve frequency-shifted feedback pulse generation with frequency tuning over a 215 nm range. The laser operates on the 3.5 $μ$m transition in erbium-doped zirconium fluoride-based fiber and utilizes the dual-wavelength pumping scheme. Stable, self-starting mode-locking with a minimum pulse duration of 53 ps was measured using a two-photon absorption autocorrelator. The longest wavelength demonstrated was 3612 nm and a maximum average power of 208 mW was achieved. This is the longest wavelength rare-earth doped mode-locked fiber laser demonstrated to the best of the authors' knowledge. The broad tunability promises potential uses for environmental sensing applications.

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Ori Henderson-Sapir, Nathaniel Bawden, Matthew R. Majewski, Robert I. Woodward, David J. Ottaway, Stuart D. Jackson3. 2019-09-25. Mode-locked and tunable fiber laser at the 3.5 $μ$m band using frequency-shifted feedback. https://doi.org/10.1364/ol.45.000224

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