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arXiv · 2205.03394

Electro-optically tunable single-frequency lasing from neodymium-doped lithium niobate microresonators

Yannick Minet·Simon J. Herr·Ingo Breunig·Hans Zappe·Karsten Buse
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Abstract

Tunable light sources are a key enabling technology for many applications such as ranging, spectroscopy, optical coherence tomography, digital imaging and interferometry. For miniaturized laser devices, whispering gallery resonator lasers are a well-suited platform, offering low thresholds and small linewidths, however, many realizations suffer from the lack of reliable tuning. Rare-earth ion-doped lithium niobate offers a way to solve this issue. Here we present a single-frequency laser based on a neodymium-doped lithium niobate whispering gallery mode resonator that is tuned via the linear electro-optic effect. Using a special geometry, we suppress higher-order transverse modes and hence ensure single-mode operation. With an applied voltage of just $68\,$V, we achieve a tuning range of $3.5\,$GHz. The lasing frequency can also be modulated with a triangular control signal. The freely running system provides a frequency and power stability of better than $\Delta\nu =20\,$MHz and 6%, respectively, for a 30 minute period. This concept is suitable for full integration with existing photonic platforms based on lithium niobate.

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Yannick Minet, Simon J. Herr, Ingo Breunig, Hans Zappe, Karsten Buse. 2022-05-06. Electro-optically tunable single-frequency lasing from neodymium-doped lithium niobate microresonators. https://doi.org/10.1364/oe.463044

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