Bogoliubov Fermi surfaces from pairing of emergent $j=3/2$ fermions on the pyrochlore lattice

Shingo Kobayashi; Ankita Bhattacharya; Carsten Timm; P. M. R. Brydon

doi:10.1103/physrevb.105.134507

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arXiv · 2111.03752

Bogoliubov Fermi surfaces from pairing of emergent $j=3/2$ fermions on the pyrochlore lattice

Shingo Kobayashi·Ankita Bhattacharya·Carsten Timm·P. M. R. Brydon

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Abstract

We examine the appearance of superconductivity in the strong-coupling limit of the Hubbard model on the pyrochlore lattice. We focus upon the limit of half filling, where the normal-state band structure realizes a $j=3/2$ semimetal. Introducing doping, we show that the pairing is favored in a $J=2$ quintet $E_g$ state. The attractive interaction in this channel relies on the fact that $E_g$ pairing on the pyrochlore lattice avoids the detrimental on-site repulsion. Our calculations show that a time-reversal symmetry-breaking superconducting phase is favored, which displays Bogoliubov Fermi surfaces.

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Shingo Kobayashi, Ankita Bhattacharya, Carsten Timm, P. M. R. Brydon. 2021-11-05. Bogoliubov Fermi surfaces from pairing of emergent $j=3/2$ fermions on the pyrochlore lattice. https://doi.org/10.1103/physrevb.105.134507

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