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arXiv · 2302.04066

Time varying gratings model Hawking radiation

Simon A. R. Horsley·John B. Pendry
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Abstract

Diffraction gratings synthetically moving at trans-luminal velocities contain points where wave and grating velocities are equal. We show these points can be understood as a series of optical event horizons where wave energy can be trapped and amplified, leading to radiation from the quantum vacuum state. We calculate the spectrum of this emitted radiation, finding a quasi-thermal spectrum with features that depend on the grating profile, and an effective temperature that scales exponentially with the length of the grating, emitting a measurable flux even for very small grating contrast.

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Simon A. R. Horsley, John B. Pendry. 2023-02-08. Time varying gratings model Hawking radiation. https://arxiv.org/abs/2302.04066

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