We investigate the phase diagram of two-dimensional (2D) Hubbard model by employing the optimization variational Monte Carlo method. The 2D Hubbard model is the most simple electronic model for cuprate high-temperature superconductors. The phase diagram consists of three regions; they are antiferromagnetic insulator region, superconducting region, and the coexistent region of superconductivity and antiferromagnetism. The phase diagram obtained by numerical calculations well agrees with the experimental phase diagram for high-temperature cuprates.

中文翻译：

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强相关电子的相图和超导机理

我们通过采用优化变分蒙特卡罗方法研究二维（2D）哈伯德模型的相图。2D Hubbard模型是用于铜酸盐高温超导体的最简单的电子模型。相图包含三个区域。它们是反铁磁绝缘体区域，超导区域以及超导电性和反铁磁性的共存区域。通过数值计算获得的相图与高温铜酸盐的实验相图非常吻合。