arXiv 0803.15792008-03cond-mat.mtrl-sci

Temperature induced spin coherence dissipation in quantum dots

F. G. G. Hernandez, A. Greilich, F. Brito, M. Wiemann, D. R. Yakovlev, D. Reuter, A. D. Wieck, M. Bayer

备注：: 4 pages, 2 figures
发表信息：: Phys. Rev. B 78, 041303(R) (2008)
DOI：: 10.1103/PhysRevB.78.041303

英文摘要：

The temperature dependence of electron spin coherence in singly negatively charged (In,Ga)As/GaAs quantum dots is studied by time-resolved Faraday rotation. The decoherence time T2 is constant on a microsecond scale for temperatures below 20 K, for higher temperatures it shows a surprisingly sharp drop into the nanoseconds range. The decrease cannot be explained through inelastic scattering with phonons, and may be related with elastic scattering due to phonon-mediated fluctuations of the hyperfine interaction.

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