Spin and conductance-peak-spacing distributions in large quantum dots: a density-functional theory study.

نویسندگان

  • Hong Jiang
  • Harold U Baranger
  • Weitao Yang
چکیده

We use spin-density-functional theory to study the spacing between conductance peaks and the ground-state spin of 2D model quantum dots with up to 200 electrons. Distributions for different ranges of electron number are obtained in both symmetric and asymmetric potentials. The even/odd effect is pronounced for small symmetric dots but vanishes for large asymmetric ones, suggesting substantially stronger interaction effects than expected. The fraction of high-spin ground states is remarkably large.

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عنوان ژورنال:
  • Physical review letters

دوره 90 2  شماره 

صفحات  -

تاریخ انتشار 2003