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arXiv · 2409.11873

Macroscopic QED and noise currents in time-varying media

S. A. R. Horsley·R. K. Baker
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Abstract

Macroscopic QED (MQED) is the field theory for computing quantum electromagnetic effects in dispersive media. Here we extend MQD to treat time-varying, dispersive media. For a time dependent Drude model, we find that the expected replacement ${\epsilon}({\omega}) {\to} {\epsilon}(t,{\omega})$ within standard MQED leads to nonphysical polarization currents, becoming singular in the limit of a step change in the carrier density. We show this singular behaviour can be removed through modifying the reservoir dynamics, quantizing the resulting theory and finding the non-equilibrium, time-varying noise currents, which exhibit extra correlations due to temporal reflections within the material dynamics.

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S. A. R. Horsley, R. K. Baker. 2024-09-18. Macroscopic QED and noise currents in time-varying media. https://arxiv.org/abs/2409.11873

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