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arXiv · 2007.15132

Coherently amplifying photon production from vacuum with a dense cloud of accelerating photodetectors

Hui Wang·Miles Blencowe
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Abstract

An accelerating photodetector is predicted to see photons in the electromagnetic vacuum. However, the extreme accelerations required have prevented the direct experimental verification of this quantum vacuum effect. In this work, we consider many accelerating photodetectors that are contained within an electromagnetic cavity. We show that the resulting photon production from the cavity vacuum can be collectively enhanced such as to be measurable. The combined cavity-photodetectors system maps onto a parametrically driven Dicke-type model; when the detector number exceeds a certain critical value, the vacuum photon production undergoes a phase transition from a normal phase to an enhanced superradiant-like, inverted lasing phase. Such a model may be realized as a mechanical membrane with a dense concentration of optically active defects undergoing gigahertz flexural motion within a superconducting microwave cavity. We provide estimates suggesting that recent related experimental devices are close to demonstrating this inverted, vacuum photon lasing phase.

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Hui Wang, Miles Blencowe. 2020-07-29. Coherently amplifying photon production from vacuum with a dense cloud of accelerating photodetectors. https://doi.org/10.1038/s42005-021-00622-3

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