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arXiv · 2102.04129

Narrow Linewidth near-UV InGaN Laser Diode based on External Cavity Fiber Bragg Grating

Antoine Congar·Mathilde Gay·Georges Perin·Dominique Mammez·Jean-Claude Simon·Pascal Besnard·Julien Rouvillain·Thierry Georges·Laurent Lablonde·Thierry Robin·Stéphane Trebaol
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Abstract

We realize a fiber Bragg grating InGaN based laser diode emitting at 400 nm and demonstrate its high coherency. Thanks to the fabrication of a narrow band fiber Bragg grating in the near-UV, we can reach single-mode and single-frequency regimes for the self-injection locked diode. The device exhibits 44 dB side-mode-suppression-ratio and mW output power. Detailed frequency noise analysis reveals sub-MHz integrated linewidth and 16 kHz intrinsic linewidth. Such a narrow linewidth laser diode in the near-UV domain with a compact and low-cost design could find applications whenever coherency and interferometric resolutions are needed.

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Antoine Congar, Mathilde Gay, Georges Perin, Dominique Mammez, Jean-Claude Simon, Pascal Besnard, Julien Rouvillain, Thierry Georges, Laurent Lablonde, Thierry Robin, Stéphane Trebaol. 2021-02-08. Narrow Linewidth near-UV InGaN Laser Diode based on External Cavity Fiber Bragg Grating. https://arxiv.org/abs/2102.04129

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