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arXiv · 0802.4454

First-order spatial coherence of excitons in planar nanostructures: a k-filtering effect

L. Mouchliadis·A. L. Ivanov
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Abstract

We propose and analyze a k-filtering effect which gives rise to the drastic difference between the actual spatial coherence length of quasi-two-dimensional (quasi-2D) excitons or microcavity (MC) polaritons in planar nanostructures and that inferred from far-field optical measurements. The effect originates from the conservation of in-plane wavevector k in the optical decay of the particles in outgoing bulk photons. The k-filtering effect explains the large coherence lengths recently observed for indirect excitons in coupled quantum wells (QWs), but is less pronounced for MC polaritons at low temperatures, T<10K.

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L. Mouchliadis, A. L. Ivanov. 2008-03-04. First-order spatial coherence of excitons in planar nanostructures: a k-filtering effect. https://doi.org/10.1103/physrevb.78.033306

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