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arXiv · 2503.03958

Enhanced superconducting correlations in the Emery model and its connections to strange metallic transport and normal state coherence

Sijia Zhao·Rong Zhang·Wen O. Wang·Jixun K. Ding·Tianyi Liu·Brian Moritz·Edwin W. Huang·Thomas P. Devereaux
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Abstract

Numerical evidence for superconductivity in the single-band Hubbard model is elusive or ambiguous despite extensive study, raising the question of whether the single-band Hubbard model is a faithful low energy effective model for cuprates, and whether explicitly including the oxygen ions will recover the properties necessary for a superconducting transition. Here we show, by using numerically exact determinant quantum Monte Carlo (DQMC) simulations of the doped Emery model, that while the single-band model exhibits strikingly T-linear resistivity, the three-band model crosses the resistivity of the single-band model from above, indicating a crossover to a more metallic transport regime. The enhanced conductivity is mainly contributed by a steep increase in the diffusivity of the three-band model at the crossover, suggesting that three-band transport is more coherent than single-band transport at lower temperatures. Below the same crossover temperature in the three-band model, the pair-field susceptibility increases more steeply than at higher temperatures or when compared to the single-band model. This suggests a possible connection between superconductivity and coherent transport, and further implies that coherent transport might be necessary for a model to capture the high-temperature superconductivity observed in hole-doped cuprates.

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Sijia Zhao, Rong Zhang, Wen O. Wang, Jixun K. Ding, Tianyi Liu, Brian Moritz, Edwin W. Huang, Thomas P. Devereaux. 2025-03-05. Enhanced superconducting correlations in the Emery model and its connections to strange metallic transport and normal state coherence. https://doi.org/10.1103/bbyx-gfwl

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