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arXiv · 2503.15759

Diverse electronic topography in a distorted kagome metal LaTi3Bi4

Anup Pradhan Sakhya·Brenden R. Ortiz·Barun Ghosh·Milo Sprague·Mazharul Islam Mondal·Matthew Matzelle·Nabil Atlam·Arun K Kumay·David G. Mandrus·Jonathan D. Denlinger·Arun Bansil·Madhab Neupane
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Abstract

Recent reports on a family of kagome metals of the form LnTi3Bi4 (Ln = Lanthanide) has stoked interest due to the combination of highly anisotropic magnetism and a rich electronic structure. The electronic structure near the Fermi level is proposed to exhibit Dirac points and van Hove singularities. In this manuscript, we use angle resolved photoemission spectroscopy measurements in combination with density functional theory calculations to investigate the electronic structure of a newly discovered kagome metal LaTi3Bi4. Our results reveal multiple van Hove singularities (VHSs) with one VHS located in the vicinity of the Fermi level. We clearly observe two flat bands, which originate from the destructive interference of wave functions within the Ti kagome motif. These flat bands and VHSs originate from Ti d orbitals and are very responsive to the polarization of the incident beam. We notice a significant anisotropy in the electronic structure, resulting from the breaking of six fold rotational symmetry in this material. Our findings demonstrate this new family of Ti based kagome material as a promising platform to explore novel emerging phenomena in the wider LnTi3Bi4 (Ln= lanthanide) family of materials.

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Anup Pradhan Sakhya, Brenden R. Ortiz, Barun Ghosh, Milo Sprague, Mazharul Islam Mondal, Matthew Matzelle, Nabil Atlam, Arun K Kumay, David G. Mandrus, Jonathan D. Denlinger, Arun Bansil, Madhab Neupane. 2025-03-20. Diverse electronic topography in a distorted kagome metal LaTi3Bi4. https://doi.org/10.1103/yxk5-jy5b

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