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Raman Scattering Due to Disorder-Induced Polaritons

Lev I. Deych·M. Erementchouk·V. A. Ignatchenko
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Abstract

The selection rules for dipole and Raman activity can be relaxed due to local distortion of a crystalline structure. In this situation a dipole-inactive mode can become simultaneously active in Raman scattering and in dipole interaction with the electromagnetic field. The later interaction results in disorder-induced polaritons, which could be observed in first-order Raman spectra. We calculate scattering cross-section in the case of a material with a diamond-like average structure, and show that there exist a strong possibility of observing the disorder induced polaritons.

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Lev I. Deych, M. Erementchouk, V. A. Ignatchenko. 1999-01-26. Raman Scattering Due to Disorder-Induced Polaritons. https://arxiv.org/abs/cond-mat/9810248

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