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Journal of Photonic Materials and Technology

Four-Body Scattering of Light as a Method of Detection of Bose-Einstein Condensate of Excitons

Yuri D. Zavorotnev

Published Jan 1, 2018• 2 citations
Publisher

Abstract

Process of four-particle light scattering in molecular crystals with participation of the exciton Bose-condensate is considered. The intensities and tensor of scattering are found for this effect. The frequency and polarization characteristics of this process are studies. It is shown that the investigation of the spectrum shapes of scattered radiation allows one to find and prove the existence of the Bose-Einstein condensate of excitons.

DOI
10.11648/j.jmpt.20180401.17

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The exciton absorption and emission bands in the presence of Bose-Einstein condensation (BEC) of excitons, induced by the coherent laser radiation is considered. The laser radiation creates the coherent macroscopic polarization of the crystal, which is described as a virtual BEC of excitons. The energy spectrum of the elementary excitations as well as the probabilities of the quantum transitions depend essentially on the frequency detuning (Delta) -. The nonequilibrium occupation numbers of out-of-condensate excitons nexq arising in the presence of virtual BEC influence on the forms of absorption and emission bands.