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arXiv · 2012.05709

Parametric amplification of topological interface states in synthetic Andreev bands

Ismael Septembre·Sergei Koniakhin·Julia Meyer·Dmitry Solnyshkov·Guillaume Malpuech
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Abstract

A driven-dissipative nonlinear photonic system (e.g. exciton-polaritons) can operate in a gapped superfluid regime. We theoretically demonstrate that the reflection of a linear wave on this superfluid is an analogue of the Andreev reflection of an electron on a superconductor. A normal region surrounded by two superfluids is found to host Andreev-like bound states. These bound states form topological synthetic bands versus the phase difference between the two superfluids. Changing the width of the normal region allows to invert the band topology and to create "interface" states. Instead of demonstrating a linear crossing, synthetic bands are attracted by the non-linear non-Hermitian coupling of bosonic systems which gives rise to a self-amplified strongly occupied topological state.

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Ismael Septembre, Sergei Koniakhin, Julia Meyer, Dmitry Solnyshkov, Guillaume Malpuech. 2020-12-10. Parametric amplification of topological interface states in synthetic Andreev bands. https://doi.org/10.1103/physrevb.103.214504

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