Comment on "Constraints on pairings in the Hubbard model"

Abstract

We show that Shi's conclusion about the singlet pairing in the Hubbard model at strong-coupling limit [Phys. Rev. B 51, 16 619 (1995)] is wrong. The singlet pairing is related to many-particle correlated pairings. There generally is no exact identity among the singlet pairing functions. We give an intuitive argument that the nearest-neighbor ${\mathit{d}}_{{\mathit{x}}^{2}\mathrm{\ensuremath{-}}{\mathit{y}}^{2}}$-wave pairing is the predominant one in the doped Hubbard model. \textcopyright{} 1996 The American Physical Society.