Transport study of the wormhole effect in three-dimensional topological insulators

TL;DR

This paper investigates the transport phenomena induced by the wormhole effect in three-dimensional topological insulators, demonstrating how wormhole interference influences conductance and proposing novel topological devices.

Contribution

It reveals how the wormhole effect introduces exotic transport behaviors and proposes practical devices utilizing wormhole degrees of freedom in topological insulators.

Findings

Conductance oscillates with Fermi energy due to wormhole interference.

Number of wormholes modulates differential conductance via a $ ext{Z}_2$ mechanism.

Proposes wormhole switch and traversable wormhole devices for applications.

Abstract

Inside a three-dimensional strong topological insulator, a tube with $h/2e$ magnetic flux carries a pair of protected one-dimensional linear fermionic modes. This phenomenon is known as the "wormhole effect". In this work, we find that the "wormhole effect", as a unique degree of freedom, introduces exotic transport phenomena and thus manipulates the transport properties of topological insulators. Our numerical results demonstrate that the transport properties of a double-wormhole system can be manipulated by the wormhole interference. Specifically, the conductance and local density of states both oscillate with the Fermi energy due to the interference between the wormholes. Furthermore, by studying the multi-wormhole systems, we find that the number of wormholes can also modulate the differential conductance through a $\mathbb{Z}$$_{2}$ mechanism. Finally, we propose two types of topological devices in real applications, the "wormhole switch" device and the "traversable wormhole" device, which can be finely tuned by controlling the wormhole degree of freedom.