Nondiffusive excitonic transport in GaAs and the effects of momentum scattering.
نویسندگان
چکیده
Measurements of exciton transport using frequency-domain nearly degenerate four-wave mixing ~NDFWM! show a failure of Fick’s law and near-ballistic excitonic motion for scale lengths less than 10 mm. A solution of the Boltzmann transport equation assuming a simple momentum-changing collision model is in agreement with the observed NDFWM line shapes and apparent subquadratic dependence on inverse scale length. The measurements show the surprising result that exciton-exciton interactions lead to a large increase in exciton linewidth with little corresponding change in exciton center-of-mass momentum, unlike exciton interactions with phonons and impurities.
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عنوان ژورنال:
- Physical review. B, Condensed matter
دوره 54 16 شماره
صفحات -
تاریخ انتشار 1996