Selective branching, quenching, and converting of topological modes

TL;DR

This paper explores how topological modes in various systems can be selectively manipulated through branching, quenching, and converting, enabling new transport effects and potential applications in topological materials.

Contribution

It introduces a framework for controlling topological modes via junctions and dynamic extensions, revealing novel effects like transistor-like behavior in artificial topological systems.

Findings

Creating junctions of $$-flux chains induces new transport phenomena.

Dynamic extension of flux chains can produce stop-and-go effects.

Active biasing of branches enables controllable topological mode manipulation.

Abstract

A salient feature of topological phases are surface states and many of the widely studied physical properties are directly tied to their existence. Although less explored, a variety of topological phases can however similarly be distinguished by their response to localized flux defects, resulting in the binding of modes whose stability can be traced back to that of convectional edge states. The reduced dimensionality of these objects renders the possibility of arranging them in distinct geometries, such as arrays that branch or terminate in the bulk. We show that the prospect of hybridizing the modes in such new kinds of channels poses profound opportunities in a dynamical context. In particular, we find that creating junctions of $\pi$-flux chains or extending them as function of time can induce transistor and stop-and-go effects. Pending controllable initial conditions certain branches of the extended defect array can be actively biased. Discussing these physical effects within a generally applicable framework that relates to a variety of established artificial topological materials, such as mass-spring setups and LC circuits, our results offer an avenue to explore and manipulate new transport effects that are rooted in the topological characterization of the underlying system.