Quantized charge fractionalization at quantum Hall Y junctions in the disorder-dominated regime

TL;DR

This paper demonstrates charge fractionalization at quantum Hall Y junctions in the disorder-dominated regime, revealing quantized fractionalization factors through a time-resolved scheme, advancing understanding of topological edge state transport.

Contribution

It introduces a time-resolved method to observe elementary fractionalization processes in quantum Hall edge channels, confirming quantized fractionalization factors in the disorder-dominated regime.

Findings

Fractionalization factors r=0.34±0.03 at ν=2/3 and r=0.49±0.03 at ν=2.

Quantized fractional charges of 1/3 and 1/2 are observed.

The scheme enables controlled generation and transport of fractionalized charges.

Abstract

Fractionalization is a phenomenon where an elementary excitation partitions into several pieces. This picture explains non-trivial transport through a junction of one-dimensional edge channels defined by topologically distinct quantum Hall states, for example, a hole-conjugate state at Landau-level filling factor $\nu$ = 2/3. Here we employ a time-resolved scheme to identify an elementary fractionalization process; injection of charge q from a non-interaction region into an interacting and scattering region of one-dimensional channels results in the formation of a collective excitation with charge $(1-\textit{r})\textit{q}$ by reflecting fractionalized charge $\textit{rq}$. The fractionalization factors, $\textit{r}$ = 0.34$\pm$0.03 for $\nu$ = 2/3 and $\textit{r}$ = 0.49$\pm$0.03 for $\nu$ = 2, are consistent with the quantized values of 1/3 and 1/2, respectively, which are expected in the disorder dominated regime. The scheme can be used for generating and transporting fractionalized charges with a well-defined time course along a well-defined path.