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QED in the Presence of Arbitrary Kramers-Kronig Dielectric Media

S. Scheel·D. -G. Welsch
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Abstract

The phenomenological Maxwell field is quantized for arbitrarily space- and frequency-dependent complex permittivity. The formalism takes account of the Kramers--Kronig relation and the dissipation-fluctuation theorem and yields the fundamental equal-time commutation relations of QED. Applications to the quantum-state transformation at absorbing and amplifying four-port devices and to the spontaneous decay of an excited atom in the presence of absorbing dielectric bodies are discussed.

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S. Scheel, D. -G. Welsch. 1999-07-16. QED in the Presence of Arbitrary Kramers-Kronig Dielectric Media. https://arxiv.org/abs/quant-ph/9906001

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