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Quantum dot ground state energies and spin polarizations: soft versus hard chaos

Denis Ullmo·Tatsuro Nagano·Steven Tomsovic
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Abstract

We consider how the nature of the dynamics affects ground state properties of ballistic quantum dots. We find that ``mesoscopic Stoner fluctuations'', that arise from the residual screened Coulomb interaction, are very sensitive to the degree of chaos. It leads to ground state energies and spin-polarizations whose fluctuations strongly increase as a system becomes less chaotic. The crucial features are illustrated with a model that depends on a parameter that tunes the dynamics from nearly integrable to mostly chaotic.

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Denis Ullmo, Tatsuro Nagano, Steven Tomsovic. 2002-11-19. Quantum dot ground state energies and spin polarizations: soft versus hard chaos. https://doi.org/10.1103/physrevlett.91.179901

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