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arXiv · cond-mat/0702469

Tuning Hole Mobility, Concentration, and Repulsion in High-$T_c$ Cuprates via Apical Atoms

Abstract

Using a newly developed first-principles Wannier-states approach that takes into account large on-site Coulomb repulsion, we derive the effective low-energy interacting Hamiltonians for several prototypical high-$T_c$ superconducting cuprates. The material dependence is found to originate primarily from the different energy of the apical atom $p_z$ state. Specifically, the general properties of the low-energy hole state, namely the Zhang-Rice singlet, are significantly modified by a triplet state associated with this $p_z$ state, via additional intra-sublattice hoppings, nearest-neighbor "super-repulsion", and other microscopic many-body processes. Possible implications on modulation of $T_c$, local superconducting gaps, charge distribution, hole mobility, electron-phonon interaction, and multi-layer effects are discussed.

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Wei-Guo Yin, Wei Ku. 2007-02-20. Tuning Hole Mobility, Concentration, and Repulsion in High-$T_c$ Cuprates via Apical Atoms. https://doi.org/10.1103/physrevb.79.214512

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