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arXiv · 2308.02192

Transport evidence of the three-dimensional Dirac semimetal phase in doped $\alpha$-Sn grown by molecular beam epitaxy

Yuanfeng Ding·Bingxin Li·Chen Li·Yan-Bin Chen·Hong Lu·Yan-Feng Chen
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Abstract

We report the quantum transport properties of the $\alpha$-Sn films grown on CdTe (001) substrates by molecular beam epitaxy. The $\alpha$-Sn films are doped with phosphorus to tune the Fermi level and access the bulk state. Clear Shubnikov-de Haas oscillations can be observed below 30 K and a nontrivial Berry phase has been confirmed. A nearly spherical Fermi surface has been demonstrated by angle-dependent oscillation frequencies. In addition, the sign of negative magnetoresistance which is attributed to the chiral anomaly has also been observed. These results provide strong evidence of the three-dimensional Dirac semimetal phase in $\alpha$-Sn.

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Yuanfeng Ding, Bingxin Li, Chen Li, Yan-Bin Chen, Hong Lu, Yan-Feng Chen. 2023-08-04. Transport evidence of the three-dimensional Dirac semimetal phase in doped $\alpha$-Sn grown by molecular beam epitaxy. https://arxiv.org/abs/2308.02192

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