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arXiv · 2311.05278

Evidence of electron correlation induced kink in Dirac bands in a non-symmorphic Kondo lattice system, CeAgSb2

Sawani Datta·Khadiza Ali·Rahul Verma·Bahadur Singh·Saroj P. Dash·A. Thamizhavel·Kalobaran Maiti
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Abstract

We study the behavior of Dirac fermions in the presence of electron correlation in a nonsymmorphic Kondo lattice system, CeAgSb2 employing high-resolution angle-resolved photoemission spectroscopy and first-principles calculations. Experiments reveal crossings of highly dispersive linear bands at the Brillouin zone boundary due to non-symmorphic symmetry. In addition, anisotropic Dirac cones are observed constituted by the squarenet Sb 5p states forming a diamond-shaped nodal line. The Dirac bands are linear in a wide energy range with a unusually high slope and exhibit distinct Dirac point in this highly spin-orbit coupled system. Interestingly, the linearity of the bands are preserved even after the hybridization of these states with the local Ce 4f states, which leads to a small reduction of slope via formation of a 'kink'. These results seed the emergence of an area of robust topological fermions even in presence of strong correlation.

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Sawani Datta, Khadiza Ali, Rahul Verma, Bahadur Singh, Saroj P. Dash, A. Thamizhavel, Kalobaran Maiti. 2023-11-09. Evidence of electron correlation induced kink in Dirac bands in a non-symmorphic Kondo lattice system, CeAgSb2. https://arxiv.org/abs/2311.05278

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