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Enhancement of Pairing Correlation by t' in the Two-Dimensional Extende d t-J Model

C. T. Shih·T. K. Lee·R. Eder·C. -Y. Mou·Y. C. Chen
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Abstract

We investigate the effects of the next-nearest-neighbor ($t'$) and the third-nearest-neighbor (t") hopping terms on superconductivity (SC) correlation in the 2D hole-doped extended t-J model based on the variational Monte-Carlo (VMC), mean-field (MF) calculation, and exact diagonalization (ED) method. Despite of the diversity of the methods employed, the results all point to a consistent conclusion: While the d-wave SC correlation is slightly suppressed by t' and t" in underdoped regions, it is greatly enhanced in the optimal and overdoped regions. The optimal T_c is a result upon balance of these two opposite trends.

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C. T. Shih, T. K. Lee, R. Eder, C. -Y. Mou, Y. C. Chen. 2004-01-30. Enhancement of Pairing Correlation by t' in the Two-Dimensional Extende d t-J Model. https://doi.org/10.1103/physrevlett.92.227002

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