Code CFTs and Topological Matter

Abstract

In this paper, we propose a novel framework for modeling topological phases of matter using code-based Narain conformal field theories (NCFTs). We show that the algebraic structure of the NCFTs naturally embeds into critical lattice quantum field theory, yielding emergent topological features characteristic of gapless fermionic systems with non-zero Chern numbers. We develop a new representation of construction A of code CFT in terms of root and weight lattices of Lie algebras, focusing in particular on SU(2) and SU(3). We then derive the spectrum of particle states occupying the lattice and, with the help of fermionisation techniques, demonstrate that it hosts fermionic excitations with Dirac cones akin to tight binding systems namely the Haldane model of quantum anomalous hall effect on a honeycomb geometry.