Fractional flux periodicity of a twisted planar square lattice

Fractional flux periodicity in tori made of square lattice

We present 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. 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. The...

1 5 A pr 2 00 4 1 Fractional flux periodicity in tori made of square lattice

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 to...

Fractional Flux Periodicity in doped carbon nanotubes

Fractional quantum Hall effect of lattice bosons near commensurate flux.

We study interacting bosons on a lattice in a magnetic field. When the number of flux quanta per plaquette is close to a rational fraction, the low-energy physics is mapped to a multispecies continuum model: bosons in the lowest Landau level where each boson is given an internal degree of freedom, or pseudospin. We find that the interaction potential between the bosons involves terms that do no...

Fractional excitations in the square lattice quantum antiferromagnet

Quantum magnets have occupied the fertile ground between many-body theory and low-temperature experiments on real materials since the early days of quantum mechanics. However, our understanding of even deceptively simple systems of interacting spins-1/2 is far from complete. The quantum square-lattice Heisenberg antiferromagnet (QSLHAF), for example, exhibits a striking anomaly of hitherto unkn...