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arXiv · 1004.3940

Terahertz absorption by excitonic polaritons

Carlos Andres Vera-Ciro·Alain Delgado·Augusto Gonzalez
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Abstract

We use linear response theory in order to compute the light absorption spectrum, in the terahertz band, of a polariton system composed by excitons in a quantum dot very strongly coupled to the lowest photon mode of a thin micropillar. In a thermalized (Bose condensed) system at low temperatures, the spectral function shows a peak (GDR) associated to a 1s - 2p exciton transition, enhanced by polariton effects. On the other hand, in a non-equilibrium system absorption is peaked at low energies. Thus, a measurement of terahertz absorption could give an indication of the degree of thermalization in the polariton system.

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Carlos Andres Vera-Ciro, Alain Delgado, Augusto Gonzalez. 2012-07-04. Terahertz absorption by excitonic polaritons. https://arxiv.org/abs/1004.3940

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