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arXiv · 1902.06945

Q-switched Dy:ZBLAN fiber lasers beyond 3 {\mu}m: comparison of pulse generation using acousto-optic modulation and inkjet-printed black phosphorus

R. I. Woodward·M. R. Majewski·N. Macadam·G. Hu·T. Albrow-Owen·T. Hasan·S. D. Jackson
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Abstract

We report high-energy mid-infrared pulse generation by Q-switching of dysprosium-doped fiber lasers for the first time. Two different modulation techniques are demonstrated. Firstly, using active acousto-optic modulation, pulses are produced with up to 12 {\mu}J energy and durations as short as 270 ns, with variable repetition rates from 100 Hz to 20 kHz and central wavelengths tunable from 2.97 to 3.23 {\mu}m. Experiments are supported by numerical modeling, identifying routes for improved pulse energies and to avoid multi-pulsing by careful choice of modulator parameters. Secondly, we demonstrate passive Q-switching by fabricating an inkjet-printed black phosphorus saturable absorber, simplifying the cavity and generating 1.0 {\mu}J pulses with 740 ns duration. The performance and relative merits of each modulation approach are then critically discussed. These demonstrations highlight the potential of dysprosium as a versatile gain medium for high-performance pulsed sources beyond 3 {\mu}m.

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R. I. Woodward, M. R. Majewski, N. Macadam, G. Hu, T. Albrow-Owen, T. Hasan, S. D. Jackson. 2019-02-19. Q-switched Dy:ZBLAN fiber lasers beyond 3 {\mu}m: comparison of pulse generation using acousto-optic modulation and inkjet-printed black phosphorus. https://doi.org/10.1364/oe.27.015032

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