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arXiv · 1112.2185

Terahertz excitation of a coherent three-level Λ-type exciton-polariton microcavity mode

Joseph L. Tomaino·Andrew D. Jameson·Yun-Shik Lee·Galina Khitrova·Hyatt M. Gibbs·Andrea C. Klettke·Mackillo Kira·Stephan W. Koch
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Abstract

Interactions of few-cycle terahertz pulses with the induced optical polarization in a quantum-well microcavity reveal that the lower and higher exciton-polariton modes together with the optically forbidden 2p-exciton state form a unique Λ-type three-level system. Pronounced nonlinearities are observed via time-resolved strong-terahertz and weak-optical excitation spectroscopy and explained with a fully microscopic theory. The results show that the terahertz pulses strongly couple the exciton-polariton states to the 2p-exciton state while no resonant transition between the two polariton levels is observed.

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Joseph L. Tomaino, Andrew D. Jameson, Yun-Shik Lee, Galina Khitrova, Hyatt M. Gibbs, Andrea C. Klettke, Mackillo Kira, Stephan W. Koch. 2011-12-09. Terahertz excitation of a coherent three-level Λ-type exciton-polariton microcavity mode. https://arxiv.org/abs/1112.2185

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