Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA.
Phys Rev Lett. 2013 May 24;110(21):216405. doi: 10.1103/PhysRevLett.110.216405. Epub 2013 May 22.
Recently developed numerical methods have enabled the explicit construction of the superconducting state of the Hubbard model of strongly correlated electrons in parameter regimes where the model also exhibits a pseudogap and a Mott insulating phase. d(x(2)-y(2)) symmetry superconductivity is found to occur in proximity to the Mott insulator, but separated from it by a pseudogapped nonsuperconducting phase. The superconducting transition temperature and order parameter amplitude are found to be maximal at the onset of the normal-state pseudogap. The emergence of superconductivity from the normal state pseudogap leads to a decrease in the excitation gap. All of these features are consistent with the observed behavior of the copper-oxide superconductors.
最近开发的数值方法使得能够在 Hubbard 模型中明确构建强关联电子的超导状态，该模型在参数区域中也表现出赝能隙和莫特绝缘相。在接近莫特绝缘体的地方发现了 d(x(2)-y(2)) 对称性超导性，但与它由赝能隙非超导相隔开。在正常态赝能隙开始时，超导转变温度和序参量幅度被发现达到最大值。超导性从正常态赝能隙中出现导致激发能隙减小。所有这些特征都与观察到的铜氧化物超导体的行为一致。
