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Absence of Coexistence of Superconductivity and Antiferromagnetism of the Hole-Doped Two-Dimensional Extended $t-J$ Model

C. T. Shih·Y. C. Chen·C. P. Chou·T. K. Lee
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Abstract

The possibility of coexistence of superconductivity (SC) and antiferromagnetic long range order (AFLRO) of the two-dimensional extended $t-J$ model in the very underdoped region is studied by the variational Monte-Carlo (VMC) method. In addition to using previously studied wave functions, a recently proposed new wave function generated from the half-filled Mott insulator is used. For hole-doped systems, the phase boundary between AFLRO and $d-$wave SC for the physical parameters, $J/t=0.3$, $t'/t=-0.3$ and $t''/t=0.2$, is located near hole density $δ_c = 0.06$, and there is {\it no} coexistence. The phase transition is first-order between these two homogeneous phases at $δ_c$.

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C. T. Shih, Y. C. Chen, C. P. Chou, T. K. Lee. 2004-08-19. Absence of Coexistence of Superconductivity and Antiferromagnetism of the Hole-Doped Two-Dimensional Extended $t-J$ Model. https://doi.org/10.1103/physrevb.70.220502

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