Electronic properties of kagome metal ScV6Sn6 using high field torque magnetometry

TL;DR

This study investigates the electronic structure and non-trivial topology of the kagome metal ScV6Sn6 using high-field torque magnetometry and DFT calculations, revealing Fermi surface reconstruction and Berry phase evidence of topological bands.

Contribution

It provides the first combined experimental and theoretical analysis of ScV6Sn6's electronic properties, highlighting the impact of charge density wave order on its Fermi surface and topology.

Findings

Detection of six main dHvA frequencies with high and low values

Berry phase near {} indicating non-trivial band topology

Fermi surface reconstruction in the charge density wave phase

Abstract

This work presents electronic properties of the kagome metal ScV6Sn6 using de Haas-van Alphen (dHvA) oscillations and density functional theory (DFT) calculations. The torque signal with the applied fields up to 43 T shows clear dHvA oscillations with six major frequencies, five of them are below 400 T (low frequencies) and one is nearly 2800 T (high frequency). The Berry phase calculated using the Landau level fan diagram near the quantum limit is approximately {\pi}, which suggests the non-trivial band topology in ScV6Sn6. To explain the experimental data, we computed the electronic band structure and Fermi surface using DFT in both the pristine and charge density wave (CDW) phases. Our results confirm that the CDW phase is energetically favorable, and the Fermi surface undergoes a severe reconstruction in the CDW state. Furthermore, the angular dependence of the dHvA frequencies are consistent with the DFT calculations. The detailed electronic properties presented here are invaluable for understanding the electronic structure and CDWorder in ScV6Sn6, as well as in other vanadium-based kagome systems.