Structures and physical properties of V-based kagome metals CsV$_{6}$Sb$_{6}$ and CsV$_{8}$Sb$_{12}$

TL;DR

This paper reports the discovery and structural characterization of two new V-based kagome metals, CsV6Sb6 and CsV8Sb12, which exhibit metallic and paramagnetic behaviors but lack charge density wave or superconducting states above 2 K.

Contribution

The study introduces two novel V-based kagome metals with unique structures, expanding the understanding of kagome lattice materials and their electronic properties.

Findings

CsV6Sb6 has V kagome bilayers.

CsV8Sb12 features intergrowth of 2D kagome layers and 1D V chains.

Both materials show metallic and Pauli paramagnetic behavior, no CDW or superconductivity above 2 K.

Abstract

We report two new members of V-based kagome metals CsV$_{6}$Sb$_{6}$ and CsV$_{8}$Sb$_{12}$. The most striking structural feature of CsV$_{6}$Sb$_{6}$ is the V kagome bilayers. For CsV$_{8}$Sb$_{12}$, there is an intergrowth of two-dimensional V kagome layers and one-dimensional V chains and the latter lead to the orthorhombic symmetry of this material. Further measurements indicate that these two materials exhibit metallic and Pauli paramagnetic behaviors. More importantly, different from CsV$_{3}$Sb$_{5}$, the charge density wave state and superconductivity do not emerge in CsV$_{6}$Sb$_{6}$ and CsV$_{8}$Sb$_{12}$ when temperature is above 2 K. Small magnetoresistance with saturation behavior and linear field dependence of Hall resistivity at high field and low temperature suggest that the carriers in both materials should be uncompensated with much different concentrations. The discovery of these two new V-based kagome metals sheds light on the exploration of correlated topological materials based on kagome lattice.