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Abstract Metals with kagome lattice provide bulk materials to host both the flat-band and Dirac electronic dispersions. A new family of kagome metals is recently discovered inAV6Sn6. The Dirac electronic structures of this material needs more experimental evidence to confirm. In the manuscript, we investigate this problem by resolving the quantum oscillations in both electrical transport and magnetization in ScV6Sn6. The revealed orbits are consistent with the electronic band structure models. Furthermore, the Berry phase of a dominating orbit is revealed to be aroundπ, providing direct evidence for the topological band structure, which is consistent with calculations. Our results demonstrate a rich physics and shed light on the correlated topological ground state of this kagome metal.
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Nanoscale visualization and spectral fingerprints of the charge order in ScV6Sn6 distinct from other kagome metals
Abstract Charge density waves (CDWs) in kagome metals have been tied to many exotic phenomena. Here, using spectroscopic-imaging scanning tunneling microscopy and angle-resolved photoemission spectroscopy, we study the charge order in kagome metal ScV6Sn6. The similarity of electronic band structures of ScV6Sn6and TbV6Sn6(where charge ordering is absent) suggests that charge ordering in ScV6Sn6is unlikely to be primarily driven by Fermi surface nesting of the Van Hove singularities. In contrast to the CDW state of cousin kagome metals, we find no evidence supporting rotation symmetry breaking. Differential conductance dI/dVspectra show a partial gapΔ1CO ≈ 20 meV at the Fermi level. Interestingly, dI/dVmaps reveal that charge modulations exhibit an abrupt phase shift as a function of energy at energy much higher thanΔ1CO, which we attribute to another spectral gap. Our experiments reveal a distinctive nature of the charge order in ScV6Sn6with fundamental differences compared to other kagome metals.
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- Award ID(s):
- 2216080
- PAR ID:
- 10487883
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- npj Quantum Materials
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2397-4648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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