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arXiv · 1907.01130

Nodal Line Spin-gapless Semimetals and High-quality Candidate Materials

Run-Wu Zhang·Zeying Zhang·Cheng-Cheng Liu·Yugui Yao
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Abstract

Spin-gapless semimetals (SGSMs), which generate 100\% spin polarization, are viewed as promising semi-half-metals in spintronics with high speed and low consumption. We propose and characterize a new $\mathbb{Z_{\mathrm{2}}}$ class of topological nodal line (TNL) in SGSMs. The proposed TNLSGSMs are protected by space-time inversion symmetry or glide mirror symmetry with two-dimensional (2D) fully spin-polarized nearly flat surface states. Based on first-principles calculations and effective model analysis, a series of high-quality materials with $\textit{R}\overline{3}\textit{c}$ and $\textit{R}{3}\textit{c}$ space groups are predicted to realize such TNLSGSMs (chainlike). The 2D fully spin-polarized nearly flat surface states may provide a route to achieving equal spin pairing topological superconductivity as well as topological catalysts.

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Run-Wu Zhang, Zeying Zhang, Cheng-Cheng Liu, Yugui Yao. 2019-10-26. Nodal Line Spin-gapless Semimetals and High-quality Candidate Materials. https://doi.org/10.1103/physrevlett.124.016402

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