Dynamics of Quantum Hall Interfaces

TL;DR

This paper explores the unique dynamical properties of quantum Hall interfaces, which behave like free strings unlike traditional edges, revealing new physics and potential links to string theory.

Contribution

It introduces the concept of unpinned, string-like quantum Hall interfaces and analyzes their distinct dynamical behavior compared to conventional edges.

Findings

String-like interfaces propagate freely in QH systems.

Quantum Hall interfaces exhibit different dynamics from edges.

Potential analogies between QH interfaces and string theory concepts.

Abstract

A quantum Hall (QH) interface is different from an ordinary QH edge, as the latter has its location determined by the confining potential, while the former can be unpinned and behave like a free string. In this paper, we demonstrate this difference by studying three different interfaces formed by (i) the Laughlin state and the vacuum, (ii) the Pfaffian state and the vacuum, and (iii) the Pfaffian and the anti-Pfaffian states. We find that string-like interfaces propagating freely in the QH system lead to very different dynamical properties from edges. This qualitative difference gives rise to fascinating new physics and suggests a new direction in future research on QH physics. We also discuss briefly possible analogies between QH interfaces and concepts in string theory.