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arXiv · 2307.10850

Subwavelength Raman Laser Driven by Quasi Bound State in the Continuum

Daniil Riabov·Ruslan Gladkov·Olesia Pashina·Andrey Bogdanov·Sergey Makarov
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Abstract

Raman lasers is an actively developing field of nonlinear optics aiming to create efficient frequency converters and various optical sensors. Due to the growing importance of ultracompact chip-scale technologies, there is a constant demand for optical devices miniaturization, however, the development of a nanoscale Raman laser remains a challenging endeavor. In this work, we propose a fully subwavelength Raman laser operating in visible range based on a gallium phosphide nanocylinder resonator supporting a quasi bound state in the continuum (quasi-BIC). We perform precise spectral matching of nanoparticle's high-$Q$ modes with the pump and detuned Raman emission wavelengths. As a result of our simulations, we demonstrate a design of Raman nanolaser, ready for experimental realization, with the lasing threshold expected to be as low as $P_{\mathrm{th}} \approx 21~\mathrm{mW}$. The suggested configuration, to the best of our knowledge, represents the very first prototype of a low-threshold Raman nanolaser with all the dimensions smaller than the operational wavelength.

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Daniil Riabov, Ruslan Gladkov, Olesia Pashina, Andrey Bogdanov, Sergey Makarov. 2023-07-20. Subwavelength Raman Laser Driven by Quasi Bound State in the Continuum. https://arxiv.org/abs/2307.10850

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