Calculation of the four-spin cyclic exchange in cuprates

Article

关键词: T-J MODEL;    MULTIPLE-SPIN-EXCHANGE;    SQUARE-LATTICE;    HUBBARD-MODEL;    SOLID HE-3;    SUPERCONDUCTORS;    EXCITATIONS;    T-C(MAX);    OXYGEN;    PARAMETERS;   

DOI  :  10.1103/PhysRevB.98.125118

来源: SCIE

【 摘 要 】

Starting from the three-band Hubbard model for the cuprates, we calculate analytically the four-spin cyclic exchange in the limit of infinite on-site Coulomb repulsion and zero O-O hopping t(pp) using two methods: (i) perturbation theory in t(pd)/Delta, where t(pd) is the Cu-O hopping and Delta the Cu-O charge transfer energy and (ii) exact solution of a Cu4O4 plaquette. The latter method coincides with the first to order eight in t(pd) and permits us to extend the results to t(pd)/Delta of order one. The results are relevant to recent experimental and theoretical research that relate the splitting of certain spin excitations with Delta and the superconducting critical temperature.

【 授权许可】

Free