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arXiv · 2204.00869

Entropic measure of directional emissions in microcavity lasers

Kyu-Won Park·Chang-Hyun Ju·Kabgyun Jeong
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Abstract

We propose a noble notion of the directional emission in microcavity lasers. First, Shannon entropy of the far-field profiles in the polar coordinate can quantify the degree of unidirectionality of the emission, while previous notions about the unidirectionality can not efficiently measure in the robust range against a variation of the deformation parameter. Second, a divergence angle of the directional emission is defined phenomenologically in terms of full width at half maximum, and it is barely applicable to a complicated peak structure. However, Shannon entropy of semi-marginal probability of the far-field profiles in the cartesian coordinate can present equivalent results, and moreover it is applicable to even the cases with a complicated peak structure of the emission.

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Kyu-Won Park, Chang-Hyun Ju, Kabgyun Jeong. 2022-04-02. Entropic measure of directional emissions in microcavity lasers. https://doi.org/10.1103/physreva.106.l031504

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