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arXiv · 1601.05895

Signature of chiral fermion instability in the Weyl semimetal TaAs above the quantum limit

Cheng-Long Zhang·Bingbing Tong·Zhujun Yuan·Ziquan Lin·Junfeng Wang·Jinglei Zhang·Chuan-Ying Xi·Zhong Wang·Shuang Jia·Chi Zhang
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Abstract

We report the electrical transport properties for Weyl semimetal TaAs in an intense magnetic field. Series of anomalies occur in the longitudinal magnetoresistance and Hall signals at ultra-low temperatures when the Weyl electrons are confined into the lowest Landau level. These strongly temperature-dependent anomalies are ascribed to the electron-hole pairing instability. Our measurements show that the Weyl semimetal TaAs in the ultraquantum regime provides a good platform for studying electron-electron interaction in topological nontrivial semimetals.

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Cheng-Long Zhang, Bingbing Tong, Zhujun Yuan, Ziquan Lin, Junfeng Wang, Jinglei Zhang, Chuan-Ying Xi, Zhong Wang, Shuang Jia, Chi Zhang. 2016-01-22. Signature of chiral fermion instability in the Weyl semimetal TaAs above the quantum limit. https://doi.org/10.1103/physrevb.94.205120

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