Raman scattering due to disorder-induced polaritons
نویسنده
چکیده
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. PACS numbers: 78.30-j, 63.50+x, 63.20-e.
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