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arXiv · 1801.02280

$d+id$ chiral superconductivity in a triangular lattice from trigonal bipyramidal complexes

Chen Lu·Li-Da Zhang·Xianxin Wu·Fan Yang·Jiangping Hu
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Abstract

We model the newly predicted high-$T_c$ superconducting candidates constructed by corner-shared trigonal bipyramidal complexes with an effective three-orbital tight-banding Hamiltonian and investigate the pairing symmetry of their superconducting states driven by electron-electron interactions. Our combined weak and strong coupling based calculations consistently identify the chiral $d+id$ superconductivity as the leading pairing symmetry in a wide doping range with realistic interaction parameters. This pairing state has nontrivial topological Chern-number and can host gapless chiral edge modes, and the vortex cores under magnetic field can carry Majorana zero modes.

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Chen Lu, Li-Da Zhang, Xianxin Wu, Fan Yang, Jiangping Hu. 2018-01-08. $d+id$ chiral superconductivity in a triangular lattice from trigonal bipyramidal complexes. https://doi.org/10.1103/physrevb.97.165110

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