Local probe of fractional edge states of S=1 Heisenberg spin chains

TL;DR

This paper demonstrates how advanced scanning tunneling microscopy can locally probe fractional edge states, the Haldane gap, and spin correlations in atomic-scale S=1 Heisenberg spin chains, revealing their topological properties.

Contribution

It introduces a novel experimental approach combining atomic engineering and spectroscopy to study topological edge states in individual S=1 spin chains.

Findings

Detection of fractionalized edge states at the atomic scale

Measurement of the Haldane gap using STM techniques

Observation of spin-spin correlation length in the chains

Abstract

Spin chains are among the simplest physical systems in which electron-electron interactions induce novel states of matter. Here we show that the combination of atomic scale engineering and spectroscopic capabilities of state of the art scanning tunnel microscopy enables probing the fractionalized edge states of individual atomic scale S=1 spin chains. These edge states arise from the topological order of the ground state in the Haldane phase. We also show that the Haldane gap and the spin-spin correlation length can be measured with the same technique.