Crossing-line-node semimetals: General theory and application to rare-earth trihydrides

  title={Crossing-line-node semimetals: General theory and application to rare-earth trihydrides},
  author={Shingo Kobayashi and Youichi Yamakawa and Ai Yamakage and Takumi Inohara and Yoshihiko Okamoto and Yukio Tanaka},
  journal={Physical Review B},
Multiple line nodes in energy-band gaps are found in semimetals preserving mirror-reflection symmetry. We classify possible configurations of multiple line nodes with crossing points (crossing line nodes) under point-group symmetry. Taking the spin-orbit interaction (SOI) into account, we also classify topological phase transitions from crossing-line-node Dirac semimetals to other topological phases, e.g., topological insulators and point-node semimetals. This study enables one to find crossing… 
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