Electronic properties of kagome metal ScV6Sn6 using high-field torque magnetometry

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 nontrivial 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 CDW order in ScV6Sn6, as well as in other vanadium-based kagome systems.