Quantum chaos and geodesics: towards non-euclidean photonics
Mélanie Lebental (LUMIN)
Onsite seminar + zoom (Meeting ID: 984 4152 4540, Passcode: p5WA0A).
Quantum chaos is a research field dedicated to semiclassical physics [1,2], i.e. the relationship
between a quantum system and its classical counterpart. The predictions are investigated in
any wave system, namely quantum, acoustics, microwaves, optics,… Microlasers are a good platform to implement the predictions of quantum chaos. Reciprocally, semi-classical physics provides efficient theoretical tools to optimize photonic devices, in particular the « trace formula » which describes the spectrum as a sum over periodic classical trajectories. I will review some of these results  and discuss on-going works on bifurcation theory and the corresponding microlaser experiments.
Recently it became possible to fabricate three-dimensionnal (3D) microlasers with high optical
quality by direct laser writing , in particular curved surface-like microlasers, leading to
the emerging domain of non-Euclidean photonics. Actually, the shortest path between
two points within a curved surface is not the straight line anymore, but is called a « geodesic ».
The corresponding trace formula should then be a sum over periodic geodesics. We checked this hypothesis with Möbius strip microlasers and provided experimental and numerical evidences that the laser modes were indeed located along periodic geodesics .
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Möbius Strip Microlasers: A Testbed for Non-Euclidean Photonics
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