Dephasing in Open Quantum Dots
نویسندگان
چکیده
Shape-averaged magnetoconductance (weak localization) is used for the first time to obtain the electron phase coherence time tf in open ballistic GaAs quantum dots. Values for tf in the range of temperature T from 0.34 to 4 K are found to be independent of dot area, and are not consistent with the tf ~ T22 behavior expected for isolated dots. Surprisingly, tfsT d agrees quantitatively with the predicted dephasing time for disordered two-dimensional electron systems. [S0031-9007(98)06449-7]
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