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Density functional theory of spin-polarized disordered quantum dots

K. Hirose·F. Zhou·N. Wingreen
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Abstract

Using density functional theory, we investigate fluctuations of the ground state energy of spin-polarized, disordered quantum dots in the metallic regime. To compare to experiment, we evaluate the distribution of addition energies and find a convolution of the Wigner-Dyson distribution, expected for noniteracting electrons, with a narrower Gaussian distribution due to interactions. The tird moment of the total distribution is independent of interactions, and so is predicted to decrease by a factor of 0.405 upon application of a magnetic field which transforms from the Gaussian orthogonal to the Gaussian unitary ensemble.

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K. Hirose, F. Zhou, N. Wingreen. 2000-06-29. Density functional theory of spin-polarized disordered quantum dots. https://doi.org/10.1103/physrevb.63.075301

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