论文标题
相关电子系统中超导性的相图和机制
Phase diagram and mechanism of superconductivity in a strongly correlated electron system
论文作者
论文摘要
我们通过采用优化的变异蒙特卡洛方法研究了二维（2D）哈伯德模型的相图。 2D哈伯德模型是Cuprate高温超导体的最简单的电子模型。相图由三个区域组成；它们是抗铁磁绝缘子（AFI）区域，超导区域以及超导性和抗铁症的共存区域。通过数值计算获得的相图与高温层酸盐的实验相图一致。我们主要关注$ t'$对抗铁磁（AF）相关性和AFI地区的影响。当我们包括$ t'$时，AF阶段的面积增加，因此纯$ D $ - 波SC阶段减少。随着$ | t'| $的增加，AFI阶段接近一半的填充量减少。
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 (AFI) region, superconducting (SC) region and the coexistent region of superconductivity and antiferromgantism. The phase diagram obtained by numerical calculations well agrees with the experimental phase diagram for high-temperature cuprates. We mainly focused on the effect of $t'$ on the antiferromagnetic (AF) correlation and the AFI region. The area of the AF phase increases when we include $t'$ and thus the pure $d$-wave SC phase decreases. The AFI phase near half filling decreases as $|t'|$ increases.
