We have calculated high temperature series to 12th order in inverse temperature for singlet superconducting correlation functions of the 2D $t\mathrm{\text{\ensuremath{-}}}J$ model with $s$ , ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$, and ${d}_{xy}$ symmetry pairs. Our calculations differ from previous work by removing disconnected pieces from the original four-point correlator and by treating the resulting pairing correlator as a matrix. We find the correlation length for ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$ pairing grows significantly with decreasing temperature and develops a broad peak as a function of doping around $\ensuremath{\delta}=0.25$ for $T/J=0.25$ at $J/t=0.4$ . The correlation lengths for $s$ and ${d}_{xy}$ symmetry remain small and do not display peaks. Antiferromagnetic spin correlations at low doping act to suppress the ${d}_{{x}^{2}\ensuremath{-}{y}^{x}}$ and ${d}_{xy}$ superconducting correlation lengths.We have calculated high temperature series to 12th order in inverse temperature for singlet superconducting correlation functions of the 2D $t\mathrm{\text{\ensuremath{-}}}J$ model with $s$, ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$, and ${d}_{xy}$ symmetry pairs. Our calculations differ from previous work by removing disconnected pieces from the original four-point correlator and by treating the resulting pairing correlator as a matrix. We find the correlation length for ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$ pairing grows significantly with decreasing temperature and develops a broad peak as a function of doping around $\ensuremath{\delta}=0.25$ for $T/J=0.25$ at $J/t=0.4$. The correlation lengths for $s$ and ${d}_{xy}$ symmetry remain small and do not display peaks. Antiferromagnetic spin correlations at low doping act to suppress the ${d}_{{x}^{2}\ensuremath{-}{y}^{x}}$ and ${d}_{xy}$ superconducting correlation lengths.

arXiv:cond-mat/0507430Physical Review LettersJun 19, 200610 citations

Superconducting phase of a two-chain Hubbard model

Takashi Yanagisawa, Yukihiro Shimoi, Yamaji K.

The exponent ${\mathit{K}}_{\mathrm{\ensuremath{\rho}}}$ and pair-field-correlation functions are calculated for a two-chain Hubbard model with an exact numerical diagonalization method. Our calculations clearly indicate that a superconducting phase appears for a wide range of Coulomb strength, where ${\mathit{K}}_{\mathrm{\ensuremath{\rho}}}$ and pair-field correlation functions are enhanced compared to the noninteracting system. The interchain pairing appears predominantly and thus our mechanism predicts an anisotropic superconductivity.The exponent ${\mathit{K}}_{\mathrm{\ensuremath{\rho}}}$ and pair-field-correlation functions are calculated for a two-chain Hubbard model with an exact numerical diagonalization method. Our calculations clearly indicate that a superconducting phase appears for a wide range of Coulomb strength, where ${\mathit{K}}_{\mathrm{\ensuremath{\rho}}}$ and pair-field correlation functions are enhanced compared to the noninteracting system. The interchain pairing appears predominantly and thus our mechanism predicts an anisotropic superconductivity.

Physical review. B, Condensed matterAug 1, 199533 citations

Superconductivity in the presence of correlations

E.J. Calegari, José Jesús Rodríguez-Núñez

Physics Letters ANov 4, 20153 citations

Superconductivity due to correlation effects

D. Schmeltzer

Physica C SuperconductivityJun 1, 19882 citations

Configuration-interaction approach to the two-dimensional Hubbard model near half-filling

Barry Friedman, Gregory Levine

The two-dimensional Hubbard model near half-filling is studied using a configuration-interaction method. Superconducting order-parameter and spin-spin correlation functions are calculated as functions of distance to probe for superconductivity and antiferromagnetism. Consistent with our previous results, these more extensive calculations point toward d-wave superconductivity in the ground state of the two-dimensional repulsive Hubbard model. The d-wave correlations tend to increase with interaction strength, size of the state space used in the calculation, and doping away from half-filling. The superconducting correlations on the Fermi surface are interpreted as d-wave pairing between spin density-wave quasiparticles.The two-dimensional Hubbard model near half-filling is studied using a configuration-interaction method. Superconducting order-parameter and spin-spin correlation functions are calculated as functions of distance to probe for superconductivity and antiferromagnetism. Consistent with our previous results, these more extensive calculations point toward d-wave superconductivity in the ground state of the two-dimensional repulsive Hubbard model. The d-wave correlations tend to increase with interaction strength, size of the state space used in the calculation, and doping away from half-filling. The superconducting correlations on the Fermi surface are interpreted as d-wave pairing between spin density-wave quasiparticles.

Physical review. B, Condensed matterApr 15, 19974 citations

We have calculated high temperature series to 12th order in inverse temperature for singlet superconducting correlation functions of the 2D $t\mathrm{\text{\ensuremath{-}}}J$ model with

s

, ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$, and

{d}_{xy}

symmetry pairs. Our calculations differ from previous work by removing disconnected pieces from the original four-point correlator and by treating the resulting pairing correlator as a matrix. We find the correlation length for ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}$ pairing grows significantly with decreasing temperature and develops a broad peak as a function of doping around $\ensuremath{\delta}=0.25$ for

T/J=0.25

J/t=0.4

. The correlation lengths for

s

and

{d}_{xy}

symmetry remain small and do not display peaks. Antiferromagnetic spin correlations at low doping act to suppress the ${d}_{{x}^{2}\ensuremath{-}{y}^{x}}$ and

{d}_{xy}

superconducting correlation lengths.