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arXiv · 2012.10709

Spatial and Spectral Mode-Selection Effects in Topological Lasers with Frequency-Dependent Gain

Matteo Seclì·Tomoki Ozawa·Massimo Capone·Iacopo Carusotto
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Abstract

We develop a semiclassical theory of laser oscillation into a chiral edge state of a topological photonic system endowed with a frequency-dependent gain. As an archetypal model of this physics, we consider a Harper-Hofstadter lattice embedding population-inverted two-level atoms as gain material. We show that a suitable design of the spatial distribution of gain and of its spectral shape provides flexible mode selection mechanisms that can stabilize single-mode lasing into an edge state. Implications of our results for recent experiments are outlined.

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Matteo Seclì, Tomoki Ozawa, Massimo Capone, Iacopo Carusotto. 2020-12-19. Spatial and Spectral Mode-Selection Effects in Topological Lasers with Frequency-Dependent Gain. https://doi.org/10.1063/5.0041124

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