Study of the electronic properties of topological kagome metals YV$_6$Sn$_6$ and GdV$_6$Sn$_6$

TL;DR

This study synthesizes and characterizes YV$_6$Sn$_6$ and GdV$_6$Sn$_6$, revealing their topological electronic properties, magnetic behaviors, and potential for tuning magnetic and topological interplay through rare-earth substitution.

Contribution

It provides the first detailed experimental and theoretical analysis of YV$_6$Sn$_6$ and GdV$_6$Sn$_6$, highlighting their topological metallic nature and magnetic properties.

Findings

GdV$_6$Sn$_6$ shows low-temperature magnetic order of Gd spins.

Both compounds are $ ext{Z}_2$ topological metals with high mobility.

The compounds exhibit multiband transport and potential for tuning magnetic-topological interplay.

Abstract

The synthesis and characterization of vanadium-based kagome metals YV$_6$Sn$_6$ and GdV$_6$Sn$_6$ are presented. X-ray diffraction, magnetization, magnetotransport, and heat capacity measurements reveal an ideal kagome network of V-ions coordinated by Sn and separated by triangular lattice planes of rare-earth ions. The onset of low-temperature, likely noncollinear, magnetic order of Gd spins is detected in GdV$_6$Sn$_6$, while V-ions in both compounds remain nonmagnetic. Density functional theory calculations are presented modeling the band structures of both compounds, which can be classified as $\mathbb{Z}_2$ topological metals in the paramagnetic state. Both compounds exhibit high mobility, multiband transport and present an interesting platform for controlling the interplay between magnetic order associated with the $R$-site sublattice and nontrivial band topology associated with the V-based kagome network. Our results invite future exploration of other $R$V$_6$Sn$_6$ ($R$=rare earth) variants where this interplay can be tuned via $R$-site substitution.