Fractional topological phases in three-dimensional coupled-wire systems

TL;DR

This paper demonstrates that three-dimensional coupled-wire systems can host fractional topological phases with protected edge states, exotic phase transitions, and potential critical phases, expanding understanding of topological matter.

Contribution

It introduces fractional topological phases in 3D coupled-wire systems, revealing new phases, phase transitions, and potential critical states beyond previous integer-based models.

Findings

Existence of fractional topological phases with protected edge states

Identification of exotic quantum phase transitions between phases

Proposal of an extended critical phase separating gapped phases

Abstract

It is shown that three-dimensional systems of coupled quantum wires support fractional topological phases composed of closed loops and open planes of two-dimensional fractional quantum Hall subsystems. These phases have topologically protected edge states, and are separated by exotic quantum phase transitions corresponding to a rearrangement of fractional quantum Hall edge modes. Some support for the existence of an extended exotic critical phase separating the bulk gapped fractional topological phases is given. Without electron-electron interactions, similar but unfractionalized bulk gapped phases based on coupled integer quantum Hall states exist. They are separated by an extended critical Weyl semimetal phase.