Andreev reflection in the fractional quantum Hall effect

TL;DR

This paper investigates Andreev-like reflection processes at interfaces involving fractional quantum Hall states, revealing how quasiparticles decay and transfer charge across junctions, advancing understanding of quantum Hall edge phenomena.

Contribution

It introduces a classification of interface processes in the strong coupling limit, highlighting an analogy to Andreev reflection in superconductor interfaces.

Findings

Quasiparticle decay into quasiholes and charge excitations at FQH interfaces.

Identification of an Andreev-like reflection process in FQH systems.

Enhanced understanding of charge transfer mechanisms at quantum Hall interfaces.

Abstract

We study the reflection of electrons and quasiparticles on point-contact interfaces between fractional quantum Hall (FQH) states and normal metals (leads), as well as interfaces between two FQH states with mismatched filling fractions. We classify the processes taking place at the interface in the strong coupling limit. In this regime a set of quasiparticles can decay into quasiholes on the FQH side and charge excitations on the other side of the junction. This process is analogous to an Andreev reflection in normal-metal/superconductor (N-S) interfaces.