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Spin and Conductance-Peak-Spacing Distributions in Large Quantum Dots: A Density Functional Theory Study

Hong Jiang·Harold U. Baranger·Weitao Yang
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Abstract

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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Hong Jiang, Harold U. Baranger, Weitao Yang. 2002-08-07. Spin and Conductance-Peak-Spacing Distributions in Large Quantum Dots: A Density Functional Theory Study. https://doi.org/10.1103/physrevlett.90.026806

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