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arXiv · 2301.11876

Influence of Local Correlations on the "Homogeneous Insulator-Superconductor" Transition in the Domain Boundaries of the Charge-Order Phase of a 2D System of a Mixed Valence

V. V. Konev·V. A. Ulitko·D. N. Yasinskaya·Yu. D. Panov·A. S. Moskvin
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Abstract

It is demonstrated in the (pseudo)spin S=1 formalism that the structure of antiphase domain boundaries in the phase of charge ordering of a mixed-valence system of the Cu1+, 2+, 3+ "triplet" type in cuprates on a two-dimensional square lattice depends to a considerable extent on on-site correlation parameter U. The results of computer modeling on large square lattices illustrate the change in the boundary structure (from a homogeneous monovalent nonconducting structure of the Cu2+ type to a filamentary superconducting one) induced by a relatively small variation of positive U values.

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V. V. Konev, V. A. Ulitko, D. N. Yasinskaya, Yu. D. Panov, A. S. Moskvin. 2023-01-27. Influence of Local Correlations on the "Homogeneous Insulator-Superconductor" Transition in the Domain Boundaries of the Charge-Order Phase of a 2D System of a Mixed Valence. https://doi.org/10.1134/s1063783418110136

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