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arXiv · 2012.13463

Steady-state superfluidity of light in a tunable cavity at room temperature

G. Keijsers·Z. Geng·K. J. H. Peters·M. Wouters·S. R. K. Rodriguez
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Abstract

Light in a nonlinear cavity is expected to flow without friction -- like a superfluid -- under certain conditions. Until now, part-light part-matter (i.e., polariton) superfluids have been observed either at liquid helium temperatures in steady state, or at room temperature for sub-picosecond timescales. Here we report signatures of superfluid cavity photons (not polaritons) for the first time. When launching a photon fluid against a defect, we observe a suppression of backscattering above a critical intensity and below a critical velocity. Room-temperature and steady-state photon superfluidity emerges thanks to the strong thermo-optical nonlinearity of our oil-filled cavity. Numerical simulations qualitatively reproduce our experimental observations, and reveal how a viscous photon fluid reorganizes into a superfluid within the thermal relaxation time of the oil. Our results establish thermo-optical nonlinear cavities as platforms for probing photon superfluidity at room temperature, and offer perspectives for exploring superfluidity in arbitrary potential landscapes using structured mirrors.

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physics.opticscond-mat.othernlin.AOphysics.flu-dynquant-ph

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G. Keijsers, Z. Geng, K. J. H. Peters, M. Wouters, S. R. K. Rodriguez. 2020-12-24. Steady-state superfluidity of light in a tunable cavity at room temperature. https://arxiv.org/abs/2012.13463

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