Huscroft C, Jarrell M, Maier T, Moukouri S, Tahvildarzadeh AN
Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221-0011.
Phys Rev Lett. 2001 Jan 1;86(1):139-142. doi: 10.1103/PhysRevLett.86.139.
We study the pseudogaps in the spectra of the 2D Hubbard model using both finite-size and dynamical cluster approximation (DCA) quantum Monte Carlo calculations. At half-filling, a charge pseudogap, accompanied by non-Fermi-liquid behavior in the self-energy, is shown to persist in the thermodynamic limit. The DCA (finite-size) method systematically underestimates (overestimates) the width of the pseudogap. A spin pseudogap is not seen at half-filling. At finite doping, a divergent d-wave pair susceptibility is observed.
我们使用有限尺寸和动态团簇近似（DCA）量子蒙特卡罗计算方法研究二维哈伯德模型光谱中的赝能隙。在半填充时，一个电荷赝能隙，伴随着自能中的非费米液体行为，被证明在热力学极限下持续存在。DCA（有限尺寸）方法系统性地低估（高估）了赝能隙的宽度。在半填充时未观察到自旋赝能隙。在有限掺杂时，观察到d波对磁化率发散。
