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arXiv · 2403.17737

Dirac Dispersions and Fermi Surface Nesting in LaCuSb$_{2}$

Marcin Rosmus·Natalia Olszowska·Zbigniew Bukowski·Przemysław Piekarz·Andrzej Ptok·Paweł Starowicz
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Abstract

LaCuSb$_{2}$ is a superconductor with a transition temperature of about $T_\text{c} = 0.9$K and is a potential platform where Dirac fermions can be experimentally observed. In this paper, we report systematic high-resolution studies of its electronic structure using the angle-resolved photoemission spectroscopy (ARPES) technique supported by the DFT calculation. The Fermi surface consists of four branches, of which the two inner ones are more 3-dimensional and the theoretical calculations reproduce well the experiment. We observe several linear dispersions forming Dirac-like structures. The nodal lines are present in the system along ${\text{M}}$-${\text{A}}$ and ${\text{X}}$-${\text{R}}$ and Dirac crossings along ${\text{X}}$-${\text{R}}$ are observed by ARPES. Finally, the nesting between external Fermi surface pockets, which corresponds to charge density wave (CDW) modulation vector is enhanced in LaCuSb$_{2}$ as compared to LaAgSb$_{2}$, while CDW appears in the latter system.

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Marcin Rosmus, Natalia Olszowska, Zbigniew Bukowski, Przemysław Piekarz, Andrzej Ptok, Paweł Starowicz. 2024-03-26. Dirac Dispersions and Fermi Surface Nesting in LaCuSb$_{2}$. https://doi.org/10.1016/j.jallcom.2024.175298

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