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Theory of Luminescence Spectra of High-Density Electron-Hole Systems: Crossover from Excitonic Bose-Einstein Condenstation to Electron-Hole BCS State

T. J. Inagaki·M. Aihara·A. Takahashi
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Abstract

We present a unified theory of luminescence spectra for highly excited semiconductors, which is applicable both to the electron-hole BCS state and to the exciton Bose-Einstein condensate. The crossover behavior between electron-hole BCS state and exciton Bose-Einstein condensate clearly manifests itself in the calculated luminescence spectra. The analysis is based on the Bethe-Salpeter equation combined with the generalized random-phase-approximation, which enables us to consider the multiple Coulomb scattering and the quantum fluctuation associated with the center-of-mass motion of electron-hole pairs. In the crossover regime, the calculated spectra are essentially different from results obtained by the BCS-like mean-field theory and the interacting Boson model. In particular, it is found that the broad spectrum, arising from the recombination of electron-hole BCS state, splits into the P- and P_2-luminescence bands with decreasing the particle density. The dependence of these bands on the carrier density is in good agreement with experiments for highly excited semiconductors.

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T. J. Inagaki, M. Aihara, A. Takahashi. 2000-06-19. Theory of Luminescence Spectra of High-Density Electron-Hole Systems: Crossover from Excitonic Bose-Einstein Condenstation to Electron-Hole BCS State. https://doi.org/10.1016/s0038-1098(00)00256-8

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