Fractional periodic persistent current in a twisted normal metal loop: an exact result

TL;DR

This paper demonstrates that twisting a normal metal loop can induce fractional periodicity in persistent currents, with the period depending on the number of twists, revealing a new control mechanism in quantum systems.

Contribution

It introduces a novel mechanism for controlling persistent current periodicity through twisting, showing fractional periodicity dependent on the number of twists in the loop.

Findings

Persistent current periodicity can be fractionalized as /p with twists.

The fractional periodicity depends on the number of twists in the loop.

The study provides an exact theoretical result using a tight-binding model.

Abstract

We explore a novel mechanism for control of periodicity in persistent current in a twisted normal metal loop threaded by a magnetic flux $\phi$. A simple tight-binding model is used to describe the system. Quite interestingly we see that, depending on the number of twist $p$, the persistent current exhibits $\phi_0/p$ ($\phi_0=ch/e$, the elementary flux-quantum) periodicity. Such fractional periodicity provides a new finding in the study of persistent current.