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On the equivalence of the Langevin and auxiliary field quantization methods for absorbing dielectrics

A. Tip·L. Knoll·S. Scheel·D. -G. Welsch
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Abstract

Recently two methods have been developed for the quantization of the electromagnetic field in general dispersing and absorbing linear dielectrics. The first is based upon the introduction of a quantum Langevin current in Maxwell's equations [T. Gruner and D.-G. Welsch, Phys. Rev. A 53, 1818 (1996); Ho Trung Dung, L. Knöll, and D.-G. Welsch, Phys. Rev. A 57, 3931 (1998); S. Scheel, L. Knöll, and D.-G. Welsch, Phys. Rev. A 58, 700 (1998)], whereas the second makes use of a set of auxiliary fields, followed by a canonical quantization procedure [A. Tip, Phys. Rev. A 57, 4818 (1998)]. We show that both approaches are equivalent.

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A. Tip, L. Knoll, S. Scheel, D. -G. Welsch. 2000-11-02. On the equivalence of the Langevin and auxiliary field quantization methods for absorbing dielectrics. https://doi.org/10.1103/physreva.63.043806

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