Experimental and theoretical study of the correlated compound YbCdSn: Evidence for large magnetoresistance and mass enhancement

TL;DR

This study investigates YbCdSn, revealing strong electron correlations that cause large magnetoresistance, mass enhancement, and topological semimetal features, combining experimental magnetotransport data with theoretical band structure analysis.

Contribution

It provides the first combined experimental and theoretical evidence of correlated topological semimetal behavior in YbCdSn, highlighting electron correlation effects on its properties.

Findings

YbCdSn exhibits large nonsaturating magnetoresistance.

The compound shows evidence of electron correlations through susceptibility and heat capacity.

Band structure calculations suggest YbCdSn is a topological nodal-line semimetal.

Abstract

The unusual features of topological semimetals arise from its nontrivial band structure. The impact of strong electron correlations on the topological states remains largely unexplored in real materials. Here, we report the magnetotransport properties of YbCdSn single crystals. We found two fundamental experimental evidences of electron correlations through magnetic susceptibility and specific heat. The electron correlations in this compound lead to an intermediate valence state and enhance the effective mass of the charge carriers. This correlated state exhibits large nonsaturating magnetoresistance, low carrier density, magnetic field induced metal-semiconductor-like crossover and a plateau in resistivity at low temperatures. This compound also shows a cusp-like magnetoconductivity at low magnetic field which indicates the presence of weak antilocalization effect. Our band structure calculations of Yb$^{2+}$ state predict YbCdSn to be a topological nodal-line semimetal.