de Haas-van Alphen effect and the first-principles study of the possible topological stannide Cu$_3$Sn

TL;DR

This study combines magnetotransport measurements, de Haas-van Alphen oscillations, and first-principles calculations to investigate Cu$_3$Sn, revealing potential topological properties similar to Ag$_3$Sn, and suggesting it hosts topological Dirac fermions.

Contribution

It provides the first combined experimental and theoretical evidence of nontrivial topological electronic states in Cu$_3$Sn, a stannide related to known topological semimetals.

Findings

Observation of clear dHvA oscillations at low fields and temperatures.

Identification of multiple quantum oscillation frequencies indicating complex Fermi surfaces.

First-principles calculations showing a nonzero $ ext{Z}_2$ topological index.

Abstract

The quest for quantum materials with diverse symmetry-protected topological states has been the focus of recent research interest, primarily due to their fascinating physical properties and the potential technological utility. In this work, we report on the magnetotransport, de Haas-van Alphen (dHvA) oscillations, and the first-principles calculations of the stannide Cu$_3$Sn that is isostructural with the recently reported topological semimetal Ag$_3$Sn. The magnetoresistance was found to vary quasi-linearly in field. Clear dHvA oscillations were observed under a field as low as 1 Tesla at 2 K, with three major oscillation frequencies $F_{\alpha}$=8.74 T, $F_{\beta}$=150.19 T and $F_{\gamma}$=229.66 T and extremely small effective masses. The analysis of dHvA quantum oscillations revealed a possible nonzero Berry phase, suggestive of the nontrivial band topology. The corroborating evidence for the nontrivial electronic topology also comes from the first-principles calculations which yield a nonzero $\mathbb{Z}_2$ topological index. These results collectively suggest that Cu$_3$Sn, in analogy to its homologue Ag$_3$Sn, may be another intermetallic stannide hosting topological Dirac fermions.