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arXiv · 0804.2418

Electron-spin beat susceptibility of excitons in semiconductor quantum wells

N H. Kwong·S. Schumacher·R. Binder
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Abstract

Recent time-resolved differential transmission and Faraday rotation measurements of long-lived electron spin coherence in quantum wells displayed intriguing parametric dependencies. For their understanding we formulate a microscopic theory of the optical response of a gas of optically incoherent excitons whose constituent electrons retain spin coherence, under a weak magnetic field applied in the quantum well's plane. We define a spin beat susceptibility and evaluate it in linear order of the exciton density. Our results explain the many-body physics underlying the basic features observed in the experimental measurements.

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N H. Kwong, S. Schumacher, R. Binder. 2008-04-15. Electron-spin beat susceptibility of excitons in semiconductor quantum wells. https://arxiv.org/abs/0804.2418

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