Magnetotransport properties of the topological nodal-line semimetal CaCdSn

TL;DR

This study investigates the topological nodal-line semimetal CaCdSn, revealing its electronic structure, high mobility, and large magnetoresistance, which are linked to its nontrivial band topology and potential for novel transport phenomena.

Contribution

It provides the first detailed magnetotransport analysis of CaCdSn, combining first-principles calculations with experimental data to uncover its topological properties and transport behavior.

Findings

CaCdSn hosts a single nodal loop around the Γ point.

Exhibits extremely large, quasilinear, non-saturating magnetoresistance.

Shows high carrier mobility (~3.44×10^4 cm^2V^{-1}s^{-1})

Abstract

Topological nodal-line semimetals support protected band crossings which form nodal lines or nodal loops between the valence and conduction bands and exhibit novel transport phenomena. Here we address the topological state of the nodal-line semimetal candidate material, CaCdSn, and report magnetotransport properties of its single crystals grown by the self-flux method. Our first-principles calculations show that the electronic structure of CaCdSn harbors a single nodal loop around the $\Gamma$ point in the absence of spin-orbit coupling (SOC) effects. The nodal crossings in CaCdSn are found to lie above the Fermi level and yield a Fermi surface that consists of both electron and hole pockets. CaCdSn exhibits high mobility ($\mu \approx 3.44\times 10^4$ cm$^2$V$^{-1}$s$^{-1}$) and displays a field-induced metal-semiconductor like crossover with a plateau in resistivity at low temperature. We observe an extremely large and quasilinear non-saturating transverse as well as longitudinal magnetoresistance (MR) at low temperatures ($\approx 7.44\times 10^3 \%$ and $\approx 1.71\times 10^3\%$, respectively, at 4K). We also briefly discuss possible reasons behind such a large quasilinear magnetoresistance and its connection with the nontrivial band structure of CaCdSn.