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QED in dispersing and absorbing media

Ludwig Knoll·Stefan Scheel·Dirk-Gunnar Welsch
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Abstract

After giving an outline of the quantization scheme based on the microscopic Hopfield model of a dielectric bulk material, we show how the classical phenomenological Maxwell equations of the electromagnetic field in the presence of dielectric matter of given space- and frequency-dependent complex permittivity can be transferred to quantum theory. Including in the theory the interaction of the medium-assisted field with atomic systems, we present both the minimal-coupling Hamiltonian and the multipolar-coupling Hamiltonian in the Coulomb gauge. To illustrate the concept, we discuss the input--output relations of radiation and the transformation of radiation-field quantum states at absorbing four-port devices, and the spontaneous decay of an excited atom near the surface of an absorbing body and in a spherical micro-cavity with intrinsic material losses. Finally, we give an extension of the quantization scheme to other media such as amplifying media, magnetic media, and nonlinear media.

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Ludwig Knoll, Stefan Scheel, Dirk-Gunnar Welsch. 2003-06-26. QED in dispersing and absorbing media. https://arxiv.org/abs/quant-ph/0006121

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