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Mesoscopic fluctuations of the ground state spin of a small metal particle

P. W. Brouwer·Yuval Oreg·B. I. Halperin
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Abstract

We study the statistical distribution of the ground state spin for an ensemble of small metallic grains, using a random-matrix toy model. Using the Hartree Fock approximation, we find that already for interaction strengths well below the Stoner criterion there is an appreciable probability that the ground state has a finite, nonzero spin. Possible relations to experiments are discussed.

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P. W. Brouwer, Yuval Oreg, B. I. Halperin. 1999-07-09. Mesoscopic fluctuations of the ground state spin of a small metal particle. https://doi.org/10.1103/physrevb.60.r13977

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