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arXiv · 2110.02734

Cooper problem in a cuprate lattice

Ali Sanayei·Ludwig Mathey
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Abstract

We solve the Cooper problem in a cuprate lattice by utilizing a three-band model. We determine the ground state of a Cooper pair for repulsive on-site interactions, and demonstrate that the corresponding wave function has an orbital $d_{x^2-y^2}$ symmetry. We discuss the influence of next-nearest-neighbor tunneling on the Cooper pair solution, in particular the necessity of next-nearest-neighbor tunneling for having $d$-wave pairs for hole-doped systems. We also propose experimental signatures of the $d$-wave Cooper pairs for a cold-atom system in a cuprate lattice.

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Ali Sanayei, Ludwig Mathey. 2021-10-06. Cooper problem in a cuprate lattice. https://arxiv.org/abs/2110.02734

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