Orbital paramagnetism without density of states enhancement in nodal-line semimetal ZrSiS

TL;DR

This paper introduces a new interband mechanism explaining orbital paramagnetism in ZrSiS, a nodal-line semimetal, without requiring density of states enhancement, highlighting a potential signature of nodal lines in such materials.

Contribution

The study proposes a novel interband mechanism based on energy dispersion curvature to explain orbital paramagnetism in ZrSiS, advancing understanding of magnetic responses in nodal-line semimetals.

Findings

Orbital paramagnetism observed without density of states enhancement.

Negative curvature of energy dispersions explains the anomalous response.

Orbital paramagnetism serves as a hallmark for nodal-line materials.

Abstract

Unconventional orbital paramagnetism without enhanced density of states was recently discovered in the nodal-line semimetal ZrSiS. We propose a novel interband mechanism, linked to the negative curvature of energy dispersions, which successfully accounts for the observed anomalous response. This negative curvature originates from energy variation along the nodal line, inherent in realistic nodal-line materials. Our results suggest that such orbital paramagnetism provides strong evidence for the presence of nodal lines in ZrSiS, and serves as a hallmark of other nodal-line materials.