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arXiv · 2402.07486

Travelling wave amplification in stationary gratings

S. A. R. Horsley·J. B. Pendry
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Abstract

We show that a grating amplitude stationary in space but oscillating in time can be accurately modelled as a set of independent gratings travelling in opposite directions, interacting almost exclusively with waves travelling in the same direction. This structure reproduces the key features of travelling gratings: amplification of a wave at points where the local wave speed equals the grating velocity. The same field compression and photon production is evident when even a single Fourier component of the grating profile has a velocity that matches the local wave speed. We speculate that these stationary but oscillating gratings may prove easier to realise experimentally than travelling gratings.

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S. A. R. Horsley, J. B. Pendry. 2024-02-12. Travelling wave amplification in stationary gratings. https://arxiv.org/abs/2402.07486

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