Local moment formation in the superconducting state of a doped Mott insulator.
Local moment formation in the superconducting state of a doped Mott insulator.
复制标题
掺杂莫特绝缘体超导状态下的局部矩形成。
作者：
Ziqiang Wang;P. Lee
本文提出了高温超导体中杂质或铜缺陷附近局域磁矩形成的微观理论。本文采用重正化平均场理论的t-J模型，研究了自旋S=0和S=1/2扇区中d波超导（SC）态的完全自洽、空间无限制解。当重正化交换耦合超过依赖于掺杂的临界值时，我们发现从单重d波SC态到自旋二重SC态的转变。诱导S=1/2矩是交错的，并局限于周围的杂质。它产生于S=1/2节状准粒子与杂质的结合。局部态密度的计算和连接到NMR和STM实验进行了讨论。
A microscopic theory is presented for the local moment formation near a nonmagnetic impurity or a copper defect in high-Tc superconductors. We use a renormalized mean-field theory of the t-J model for a doped Mott insulator and study the fully self-consistent, spatially unrestricted solutions of the d-wave superconducting (SC) state in both the spin S=0 and S=1/2 sectors. We find a transition from the singlet d-wave SC state to a spin doublet SC state when the renormalized exchange coupling exceeds a doping dependent critical value. The induced S=1/2 moment is staggered and localized around the impurity. It arises from the binding of an S=1/2 nodal quasiparticle to the impurity. The local density of states is calculated and connections to NMR and STM experiments are discussed.