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arXiv · 2404.01389

Enhanced pair-density-wave vertices in a bilayer Hubbard model at half-filling

Fangze Liu·Xu-Xin Huang·Edwin W. Huang·Brian Moritz·Thomas P. Devereaux
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Abstract

Motivated by the pair-density-wave (PDW) state found in the one-dimensional Kondo-Heisenberg chain, we report on a determinant quantum Monte Carlo DQMC study of pair-fields for a two-dimensional half-filled Hubbard layer coupled to an itinerant, non-interacting layer with one electron per site. In a specific range of interlayer hopping, the pairing vertex associated with PDW order becomes more attractive than that for uniform d-wave pairing, although both remain subdominant to the leading antiferromagnetic correlations at half-filling. Our result sheds light on where one potentially may find a PDW state in such a model.

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Fangze Liu, Xu-Xin Huang, Edwin W. Huang, Brian Moritz, Thomas P. Devereaux. 2024-04-01. Enhanced pair-density-wave vertices in a bilayer Hubbard model at half-filling. https://doi.org/10.1103/physrevlett.133.156503

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