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arXiv · 2212.04874

Angular-dependent Andreev reflection on a polaritonic superfluid

I. Septembre·D. D. Solnyshkov·G. Malpuech
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Abstract

We study analytically an analog of the Andreev reflection at a normal-superfluid interface. The polariton gapped superfluid region is achieved by quasi-resonant optical pumping. The interacting polaritons are described with the driven-dissipative Gross-Pitaevskii equation. We find analytical formulas for the angles and amplitudes of the reflected and transmitted particles. There are limit angles and energies, above which Andreev reflection/transmission cannot be observed anymore and where the Andreev wave becomes a surface mode, exponentially localized on the interface. These properties are confirmed by solving numerically the Gross-Pitaevskii equation in simulations reproducing realistic experimental conditions.

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I. Septembre, D. D. Solnyshkov, G. Malpuech. 2022-12-09. Angular-dependent Andreev reflection on a polaritonic superfluid. https://arxiv.org/abs/2212.04874

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