Electronic exchange in quantum rings

E. Rasanen; S. Pittalis; C. R. Proetto; E. K. U. Gross

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arXiv · 0807.1868

Electronic exchange in quantum rings

E. Rasanen·S. Pittalis·C. R. Proetto·E. K. U. Gross

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Abstract

Quantum rings can be characterized by a specific radius and ring width. For this rich class of physical systems, an accurate approximation for the exchange-hole potential and thus for the exchange energy is derived from first principles. Excellent agreement with the exact-exchange results is obtained regardless of the ring parameters, total spin, current, or the external magnetic field. The description can be applied as a density functional outperforming the commonly used local-spin-density approximation, which is here explicitly shown to break down in the quasi-one-dimensional limit. The dimensional crossover, which is of extraordinary importance in low-dimensional systems, is fully captured by our functional.

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E. Rasanen, S. Pittalis, C. R. Proetto, E. K. U. Gross. 2009-02-04. Electronic exchange in quantum rings. https://arxiv.org/abs/0807.1868

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