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arXiv · 2507.02296

Symmetries of electron interactions in Hubbard models of unconventional superconductors

Sergei Urazhdin·Yiou Zhang
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Abstract

We use symmetry arguments to show that the matrix elements of electron-electron interaction on a lattice reach extrema in states composed of wavevectors near high-symmetry points of the Brillouin zone. The mechanism is illustrated by minimal models of cuprates and Fe-based superconductors, where this dependence originates from the wavevector-dependent orbital composition of wavefunctions. We discuss how these dependences can facilitate finite-momentum pairing. Our results provide symmetry-based guidance for the search for new high-temperature superconductors.

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Sergei Urazhdin, Yiou Zhang. 2025-07-03. Symmetries of electron interactions in Hubbard models of unconventional superconductors. https://arxiv.org/abs/2507.02296

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