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Fractional flux periodicity in tori made of square lattice

K. Sasaki·Y. Kawazoe·R. Saito
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Abstract

This paper describes a study on fractional flux periodicity of the ground state in planar systems made from a square lattice whose boundary is compacted into a torus. It is pointed out that, in the long length and large diameter limit of a torus, the ground-state energy and persistent currents show a fractional period of the fundamental unit of magnetic flux depending on the twist around the torus axis. We discuss the possible relationship between the twist and genus of a torus, and comment on fractional flux periodicity in a cylinder.

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K. Sasaki, Y. Kawazoe, R. Saito. 2004-04-15. Fractional flux periodicity in tori made of square lattice. https://doi.org/10.1143/ptp.111.763

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