Haurie L, Grandadam M, Pangburn E, Banerjee A, Burdin S, Pépin C
Institut de Physique Théorique, Université Paris Saclay, CEA CNRS, Orme des Merisiers, 91190 Gif-sur-Yvette Cedex, France.
Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John's, Newfoundland & Labrador A1B 3X7, Canada.
J Phys Condens Matter. 2024 Mar 27;36(25). doi: 10.1088/1361-648X/ad1e07.
We use the composite operator method (COM) to analyze the strongly correlated repulsive Hubbard model, investigating the effect of nearest-neighbor hoppings up to fourth order on a square lattice. We consider two sets of self-consistent equations, one enforcing the Pauli principle and the other imposing charge-charge, spin-spin, and pair-pair correlations using a decoupling scheme developed by Roth (1969451-9). We extract three distinct solutions from these equations: COM1 and COM2 by imposing the Pauli principle and one from Roth decoupling. An overview of the method studying the validity of particle-hole symmetry and the Luttinger theorem for each solution is presented. Additionally, we extend the initial basis to study superconductivity, concluding that it is induced by the Van Hove singularity. Finally, we include higher-order hoppings using realistic estimates for tight binding parameters and compare our results with ARPES measurements on cuprates.
我们使用复合算符方法（COM）来分析强关联排斥性哈伯德模型，研究在方形晶格上直至四阶的最近邻跳跃的影响。我们考虑两组自洽方程，一组遵循泡利原理，另一组使用罗斯（1969451 - 9）提出的解耦方案来施加电荷 - 电荷、自旋 - 自旋和配对 - 配对关联。我们从这些方程中提取出三个不同的解：通过遵循泡利原理得到的COM1和COM2，以及一个来自罗斯解耦的解。本文给出了研究每个解的粒子 - 空穴对称性和卢廷格定理有效性的方法概述。此外，我们扩展初始基来研究超导性，得出超导性是由范霍夫奇点诱导的结论。最后，我们使用紧束缚参数的实际估计值纳入高阶跳跃，并将我们的结果与铜酸盐的角分辨光电子能谱测量结果进行比较。
