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arXiv · 2411.12613

The mean field approximation for a system of triplet bosons in nickelates

V. S. Ryumshin·S. V. Nuzhin·Yu. D. Panov·A. S. Moskvin
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Abstract

Rare-earth orthonickelates RNiO3 are Jahn-Teller magnets, unstable with respect to the anti-Jahn-Teller disproportionation reaction with the formation of a system equivalent to a system of effective spin-triplet composite bosons moving in a non-magnetic lattice. Within the framework of the two-sublattice approximation, we have developed a mean field theory for a model nickelate with competition between phases of charge ordering, an antiferromagnetic insulator and a spin-triplet superconductor, and constructed phase diagrams taking into account phase separation.

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V. S. Ryumshin, S. V. Nuzhin, Yu. D. Panov, A. S. Moskvin. 2024-11-19. The mean field approximation for a system of triplet bosons in nickelates. https://doi.org/10.61011/pss.2024.07.58968.13hh

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