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Superconductivity in the two-dimensional t-J model

S. Sorella·G. B. Martins·F. Becca·C. Gazza·L. Capriotti·A. Parola·E. Dagotto
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Abstract

Using computational techniques, it is shown that pairing is a robust property of hole doped antiferromagnetic (AF) insulators. In one dimension (1D) and for two-leg ladder systems, a BCS-like variational wave function with long-bond spin-singlets and a Jastrow factor provides an accurate representation of the ground state of the t-J model, even though strong quantum fluctuations destroy the off-diagonal superconducting (SC) long-range order in this case. However, in two dimensions (2D) it is argued -- and numerically confirmed using several techniques, especially quantum Monte Carlo (QMC) -- that quantum fluctuations are not strong enough to suppress superconductivity.

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S. Sorella, G. B. Martins, F. Becca, C. Gazza, L. Capriotti, A. Parola, E. Dagotto. 2001-10-22. Superconductivity in the two-dimensional t-J model. https://doi.org/10.1103/physrevlett.88.117002

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