Chiral properties of topological-state loops

TL;DR

This paper investigates the chiral angular momentum properties of topological-state loops, revealing their potential as tunable building blocks for artificial magnets with diverse magnetic behaviors.

Contribution

It analytically demonstrates the highly chiral angular momentum quantization of topological modes in circular interfaces between different phases, linking them to spin and valley degrees of freedom.

Findings

Angular momentum exhibits highly chiral behavior.

States can be coupled to spin and valley degrees.

Loops serve as tunable building blocks for artificial magnets.

Abstract

The angular momentum quantization of chiral gapless modes confined to a circularly shaped interface between two different topological phases is investigated. By examining several different setups, we show analytically that the angular momentum of the topological modes exhibits a highly chiral behavior, and can be coupled to spin and/or valley degrees of freedom, reflecting the nature of the interface states. The energies and the magnetic moments corresponding to these states can be understood from a semiclassical picture. These loops can be viewed as building blocks for artificial magnets with tunable and highly diverse properties.