Travelling wave amplification in stationary gratings

• URL: http://arxiv.org/abs/2402.07486v1
• Date: Mon, 12 Feb 2024 08:52:03 GMT
• Title: Travelling wave amplification in stationary gratings
• Abstract summary: 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. This structure reproduces the key features of travelling gratings: amplification of a wave at points where the local wave speed equals the grating velocity.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• 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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