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arXiv · 0802.1108

Fractional periodicity and magnetism of extended quantum rings

Y. Hancock·J. Suorsa·E. Tölö·A. Harju
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Abstract

The magnetic properties and nature of the persistent current in small flux-penetrated $t-t'-U$ rings are investigated. An effective rigid-rotator description is formulated for this system, which coincides with a transition to a ferromagnetic state in the model. The criteria for the onset of effective rigid rotation is given. The model is used to understand continuum model ground-state solutions for a 2D few-particle hard-wall quantum dot, where ferromagnetic solutions are found even without the Zeeman coupling to spin. After the onset of effective rigid rotation, a 97--98% correspondence can be determined between the lattice model and continuum model eigenstate results.

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Y. Hancock, J. Suorsa, E. Tölö, A. Harju. 2008-02-08. Fractional periodicity and magnetism of extended quantum rings. https://doi.org/10.1103/physrevb.77.155103

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