Charge Fractionalization in a Mesoscopic Ring

TL;DR

This paper investigates electron fractionalization in a strongly interacting one-dimensional ring, proposing magnetic field-based measurements to distinguish true fractionalization from other effects.

Contribution

It introduces non-invasive magnetic field profile measurements as a novel way to detect and differentiate electron fractionalization in mesoscopic rings.

Findings

Magnetic-field squared profiles depend on fractionalization degree.

Proposed measures can distinguish fractionalization from superposition and classical effects.

Persistent current measurements support the differentiation method.

Abstract

We study the fractionalization of an electron tunneling into a strongly interacting electronic one-dimensional ring. As a complement to transport measurements in quantum wires connected to leads, we propose non-invasive measures involving the magnetic field profile around the ring to probe this fractionalization. In particular, we show that the magnetic-field squared produced by the electron and the power that it would induce in a detector exhibit anisotropic profiles that depend on the degree of fractionalization. We contrast true fractionalization with two other scenarios which could mimic it -- quantum superposition and classical probabilistic electron insertion. We show that the proposed field-dependent measures and those of the persistent current can distinguish between these three scenarios.