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arXiv · 2206.03486

Enhanced superconductivity by near-neighbor attraction in the doped Hubbard model

Cheng Peng·Yao Wang·Jiajia Wen·Young Lee·Thomas Devereaux·Hong-Chen Jiang
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Abstract

Recent experiment has unveiled an anomalously strong electron-electron attraction in one-dimensional copper-oxide chain Ba$_{2-x}$Sr$_x$CuO$_{3+\delta}$. While the near-neighbor electron attraction $V$ in the one-dimensional extended Hubbard chain has been examined recently, its effect in the Hubbard model beyond the one-dimensional chain remains unclear. We report a density-matrix renormalization group study of the extended Hubbard model on long four-leg cylinders on the square lattice. We find that the near-neighbor electron attraction $V$ can notably enhance the long-distance superconducting correlations while simultaneously suppressing the charge-density-wave correlations. Specifically, for a modestly strong electron attraction, the superconducting correlations become dominant over the CDW correlations with a Luttinger exponent $K_{sc}\sim 1$ and strong divergent superconducting susceptibility. Our results provide a promising way to realize long-range superconductivity in the doped Hubbard model in two dimensions. The relevance of our numerical results to cuprate materials is also discussed.

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Cheng Peng, Yao Wang, Jiajia Wen, Young Lee, Thomas Devereaux, Hong-Chen Jiang. 2022-06-07. Enhanced superconductivity by near-neighbor attraction in the doped Hubbard model. https://doi.org/10.1103/physrevb.107.l201102

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