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arXiv · 1807.03447

Ideal inner nodal chain semimetals in Li2XY (X = Ca, Ba; Y = Si, Ge) materials

Xiaoming Zhang·Lei Jin·Xuefang Dai·Guifeng Chen·Guodong Liu
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Abstract

The chain-type nodal loops in the reciprocal space can generate exotic nodal chain fermions. Here, we report that Li2XY (X = Ca, Ba; Y = Si, Ge) compounds are ideal inner nodal chain semimetals. Their band structures are composed of two connecting nodal loops with either hybrid or type-I band dispersion. The signatures of the nodal chain, such as the nontrivial surface states, are quite pronounced in these Li2XY compounds since there is only a single inner nodal chain without other extraneous bands near the Fermi level. These compounds are existing materials and ambient-stable, which is available to realize the experimental detection of inner nodal chain fermions or further the practical applications.

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Xiaoming Zhang, Lei Jin, Xuefang Dai, Guifeng Chen, Guodong Liu. 2018-07-10. Ideal inner nodal chain semimetals in Li2XY (X = Ca, Ba; Y = Si, Ge) materials. https://doi.org/10.1021/acs.jpclett.8b02204

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