Gauge fields, quantized fluxes and monopole confinement of the honeycomb lattice

TL;DR

This paper explores the topological and gauge-theoretic properties of electron hopping on the honeycomb lattice, revealing quantized fluxes, monopole solutions, and their relation to quantum Hall effects and symmetry breaking.

Contribution

It introduces a non-Abelian SO(3) gauge theory framework for the honeycomb lattice and demonstrates stable monopole solutions and flux quantization linked to topological phenomena.

Findings

Existence of two quantized Abrikosov fluxes at Dirac points.

Stable monopole and anti-monopole solutions in SO(3) gauge theory.

Relation of flux quantization to quantum Hall conductance.

Abstract

Electron hopping models on the honeycomb lattice are studied. The lattice consists of two triangular sublattices, and it is non-Bravais. The dual space has non-trivial topology. The gauge fields of Bloch electrons have the U(1) symmetry and thus represent superconducting states in the dual space. Two quantized Abrikosov fluxes exist at the Dirac points and have fluxes $2pi$ and $-2pi$, respectively. We define the non-Abelian SO(3) gauge theory in the extended 3$d$ dual space and it is shown that a monopole and anti-monoplole solution is stable. The SO(3) gauge group is broken down to U(1) at the 2$d$ boundary.The Abrikosov fluxes are related to quantized Hall conductance by the topological expression. Based on this, monopole confinement and deconfinement are discussed in relation to time reversal symmetry and QHE. The Jahn-Teller effect is briefly discussed.