Antiferromagnetism and superconductivity of the two-dimensional extended t-J model

C. T. Shih, J. J. Wu, Y. C. Chen, C. Y. Mou, C. P. Chou, R. Eder, T. K. Lee
2005 Low temperature physics (Woodbury, N.Y., Print)  
The mechanism of high-temperature superconductivity (HTS) and the correlation between the antiferromagnetic long-range order (AFLRO) and superconductivity (SC) phases are the central issues of the study of HTS theory. SC and AFLRO of the hole-doped two-dimensional extended t J model are studied by the variational Monte Carlo method. The results show that SC is greatly enhanced by the long-range hopping terms t¢ and ¢¢ t for the optimal and overdoped cases. The phase of coexisting SC and AFM in
more » ... he t J model disappears when t¢ and ¢¢ t are included. It is concluded that the extended t J model provides a more accurate description for HTS than the traditional t J model does. The momentum distribution function n( ) k and the shape of Fermi surface play critical roles for establishing the phase diagram of HTS materials.
doi:10.1063/1.2008136 fatcat:l4gpktwvf5einhnqnzsh4k7tfm