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arXiv · cond-mat/9708170

Dephasing in Open Quantum Dots

A. G. Huibers·M. Switkes·C. M. Marcus·K. Campman·A. C. Gossard
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Abstract

Shape-averaged magnetoconductance (weak localization) is used for the first time to obtain the electron phase coherence time $τ_ϕ$ in open ballistic GaAs quantum dots. Values for $τ_ϕ$ in the range of temperature T from 0.335 to 4 K are found to be independent of dot area, and are not consistent with the $τ_ϕ \propto T^{-2}$ behavior expected for isolated dots. Surprisingly, $τ_ϕ(T)$ agrees quantitatively with the predicted dephasing time for disordered two-dimensional electron systems.

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A. G. Huibers, M. Switkes, C. M. Marcus, K. Campman, A. C. Gossard. 1997-08-21. Dephasing in Open Quantum Dots. https://doi.org/10.1016/s0921-4526(98)00129-x

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