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arXiv · 1001.2174

Semifluxon degeneracy choreography in Aharonov-Bohm billiards

M V Berry·S Popescu
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Abstract

Every energy level of a charged quantum particle confined in a region threaded by a magnetic flux line with quantum flux one-half must be degenerate for some position of the semifluxon within the boundary B. This is illustrated by computations for which B is a circle and a conformal transformation of a circle without symmetry. As the shape of B is varied, two degeneracies between the same pair of levels can collide and annihilate. Degeneracy of three levels requires three shape parameters, or the positions of three semifluxons; degeneracy of N levels can be generated by int{N(N+1)/4} semifluxons. The force on the semifluxon is derived.

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M V Berry, S Popescu. 2010-01-13. Semifluxon degeneracy choreography in Aharonov-Bohm billiards. https://arxiv.org/abs/1001.2174

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