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arXiv · 0711.3981

Resonant light delay in GaN with ballistic and diffusive propagation

T. V. Shubina·M. M. Glazov·A. A. Toropov·N. A. Gippius·A. Vasson·J. Leymarie·A. Kavokin·A. Usui·J. P. Bergman·G. Pozina·B. Monemar
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Abstract

We report on a strong delay in light propagation through bulk GaN, detected by time-of-flight spectroscopy. The delay increases resonantly as the photon energy approaches the energy of a neutral-donor bound exciton (BX), resulting in a velocity of light as low as 2100 km/s. In the close vicinity of the BX resonance, the transmitted light contains both ballistic and diffusive components. This phenomenon is quantitatively explained in terms of optical dispersion in a medium where resonant light scattering by the BX resonance takes place in addition to the polariton propagation.

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T. V. Shubina, M. M. Glazov, A. A. Toropov, N. A. Gippius, A. Vasson, J. Leymarie, A. Kavokin, A. Usui, J. P. Bergman, G. Pozina, B. Monemar. 2007-11-26. Resonant light delay in GaN with ballistic and diffusive propagation. https://doi.org/10.1103/physrevlett.100.087402

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