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Local Moment Formation in the Superconducting State of a Doped Mott Insulator

Ziqiang Wang·Patrick A. Lee
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Abstract

A microscopic theory is presented for the local moment formation near a non-magnetic impurity or a copper defect in high-T_c superconductors. We use a renormalized meanfield 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 excitation to the impurity. The local density of states spectrum is calculated and connections to NMR and STM experiments are discussed.

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Ziqiang Wang, Patrick A. Lee. 2002-09-20. Local Moment Formation in the Superconducting State of a Doped Mott Insulator. https://doi.org/10.1103/physrevlett.89.217002

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