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arXiv · cond-mat/0605578

Nonlocal interactions in doped cuprates: correlated motion of Zhang-Rice polarons

Abstract

In-plane, inter-carrier correlations in hole doped cuprates are investigated by ab initio multiconfiguration calculations. The dressed carriers display features that are reminiscent of both Zhang-Rice (ZR) CuO4 singlet states and Jahn-Teller polarons. The interaction between these quasiparticles is repulsive. At doping levels that are high enough, the interplay between long-range unscreened Coulomb interactions and long-range phase coherence among the O-ion half-breathing vibrations on the ZR plaquettes may lead to a strong reduction of the effective adiabatic energy barrier associated to each polaronic state. Tunneling effects cannot be neglected for a relatively flat, multi-well energy landscape. We suggest that the coherent, superconducting quantum state is the result of such coherent quantum lattice fluctuations involving the in-plane O ions. Our findings appear to support models where the superconductivity is related to a lowering of the in-plane kinetic energy.

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BibTeXRIS

L. Hozoi, S. Nishimoto, G. Kalosakas, D. B. Bodea, S. Burdin. 2006-05-23. Nonlocal interactions in doped cuprates: correlated motion of Zhang-Rice polarons. https://doi.org/10.1103/physrevb.75.024517

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