Antiferromagnetism and pairing symmetries in two-dimensional t-J model

作者：Watanabe Tsutomu^*; Yokoyama Hisatoshi; Kobayashi Kenji

来源：Physica C-Superconductivity and Its Applications, 2010, 470: S106-S108.

DOI：10.1016/j.physc.2009.12.061

• High-T(c) cuprate
• Extended t-J model
• Variational Monte Carlo method

To elucidate systematically the interplay between antiferromagnetism (AF) and superconductivity (SC) in High-T(c) cuprates, we study the effect of the long-range transfers, t' and t '', by applying a variational Monte Carlo method to a t-J model. In the trial wave function, coexistence of SC and AF phases and contribution of long-range Cooper pairs, namely the higher harmonic components of the SC gap, are considered. Our result exhibits marked electron-hole asymmetry; for the hole-(electron-)doped case, the SC state is very stable (unstable), while the AF state is irrelevant (predominant). The coexisting phase always appears in the under-doped region, both in the hole-doped and electron-doped cases. Furthermore, the optimized long-range pairing components successfully yield the asymmetry of the gap form observed in the hole-doped and electron-doped cuprates.

• 出版日期2010-12