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arXiv · 2507.05500

YNiSn$_2$: A candidate Dirac semimetal

G. S. Freitas·C. Kaufmann Ribeiro·F. B. Carneiro·H. Pizzi·R. C. Santos·D. L. Passos·M. E. M. Ignacio·K. R. Pakuszewski·A. P. Machado·F. S. Oliveira·M. M. Piva·E. M. Bittar·C. Adriano·Y. Kopelevich·F. Ronning·J. D. Thompson·S. M. Thomas·P. F. S. Rosa·P. G. Pagliuso
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Abstract

We report the synthesis and physical properties of the new compound YNiSn$_2$, which crystallizes in the orthorhombic \textit{Cmcm} structure. The material exhibits semimetallic behavior and develops a giant positive magnetoresistance approaching 1200\% at $B = 16$ T. Pronounced de Haas-van Alphen and Shubnikov-de Haas oscillations reveal a dominant quasi-two-dimensional Fermi surface with an exceptionally small cyclotron effective mass of $m^{*} = 0.08 m{0}$, indicating light carriers and a tiny Fermi surface pocket. The strong anisotropy revealed by Shubnikov-de Haas quantum oscillation measurements highlights the low-dimensional electronic character of YNiSn$_2$, positioning it as a promising Dirac semimetal candidate.

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G. S. Freitas, C. Kaufmann Ribeiro, F. B. Carneiro, H. Pizzi, R. C. Santos, D. L. Passos, M. E. M. Ignacio, K. R. Pakuszewski, A. P. Machado, F. S. Oliveira, M. M. Piva, E. M. Bittar, C. Adriano, Y. Kopelevich, F. Ronning, J. D. Thompson, S. M. Thomas, P. F. S. Rosa, P. G. Pagliuso. 2025-07-07. YNiSn$_2$: A candidate Dirac semimetal. https://arxiv.org/abs/2507.05500

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