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Title: Nanoscale visualization and spectral fingerprints of the charge order in ScV6Sn6 distinct from other kagome metals

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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Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
npj Quantum Materials
Medium: X
Sponsoring Org:
National Science Foundation
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