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Fluctuating spin g-tensor in small metal grains

P. W. Brouwer·X. Waintal·B. I. Halperin
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Abstract

In the presence of spin-orbit scattering, the splitting of an energy level in a generic small metal grain due to the Zeeman coupling to a magnetic field B depends on the direction of B, as a result of mesoscopic fluctuations. The anisotropy is described by the eigenvalues g_j^2 (j=1,2,3) of a tensor G, corresponding to the (squares of) g-factors along three principal axes. We consider the statistical distribution of G and find that the anisotropy is enhanced by eigenvalue repulsion between the g_j.

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P. W. Brouwer, X. Waintal, B. I. Halperin. 2000-02-09. Fluctuating spin g-tensor in small metal grains. https://doi.org/10.1103/physrevlett.85.369

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