Kondo physics in antiferromagnetic Weyl semimetal Mn3+xSn1-x films

TL;DR

This study explores the emergence of Kondo physics and related topological phenomena in epitaxial Mn3+xSn1-x films, revealing how magnetic doping induces strong correlations, hybridization gaps, and novel Hall effects in an antiferromagnetic Weyl semimetal.

Contribution

It demonstrates the synthesis of Mn3+xSn1-x films with extended composition range and uncovers the development of Kondo effect and hybridization gaps in this topological material.

Findings

Kondo effect emerges with magnetic Mn doping

Hybridization energy gap opens in the material

Enhanced Hall effects and terahertz Faraday rotation observed

Abstract

Topology and strong electron correlations are crucial ingredients in emerging quantum materials, yet their intersection in experimental systems has been relatively limited to date. Strongly correlated Weyl semimetals, particularly when magnetism is incorporated, offer a unique and fertile platform to explore emergent phenomena in novel topological matter and topological spintronics. The antiferromagnetic Weyl semimetal Mn3Sn exhibits many exotic physical properties such as a large spontaneous Hall effect and has recently attracted intense interest. In this work, we report synthesis of epitaxial Mn3+xSn1-x films with greatly extended compositional range in comparison with that of bulk samples. As Sn atoms are replaced by magnetic Mn atoms, the Kondo effect, which is a celebrated example of strong correlations, emerges, develops coherence, and induces a hybridization energy gap. The magnetic doping and gap opening lead to rich extraordinary properties as exemplified by the prominent DC Hall effects and resonance-enhanced terahertz Faraday rotation.