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

摘要

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 magnetolransport properties of YbCdSn single crystals. We found two fundamental experimental evidences of electron correlations through magnetic susceptibility and specific heal. The electron correlations in this compound lead to an intermediate valence state and enhance the effective mass of the charge earners. This correlated slate 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.