Excess conductance of a spin-filtering quantum dot

  title={Excess conductance of a spin-filtering quantum dot},
  author={C. W. J. Beenakker},
  journal={Physical Review B},
The conductance G of a pair of single-channel point contacts in series, one of which is a spin filter, increases from 1/2 to 2/3 x e^2/h with more and more spin-flip scattering. This excess conductance was observed in a quantum dot by Zumbuhl et al., and proposed as a measure for the spin relaxation time T_1. Here we present a quantum mechanical theory for the effect in a chaotic quantum dot (mean level spacing Delta, dephasing time tau_phi, charging energy e^2/C), in order to answer the… Expand
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