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Origin of Spin Incommensurability in Hole-doped S=1 $\rm Y_{2-x}Ca_x Ba Ni O_5$ Chains

Andre Luiz Malvezzi·Elbio Dagotto
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Abstract

Spin incommensurability has been recently experimentally discovered in the hole-doped Ni-oxide chain compound $\rm Y_{2-x}Ca_x Ba Ni O_5$ (G. Xu {\it al.}, Science {\bf 289}, 419 (2000)). Here a two orbital model for this material is studied using computational techniques. Spin IC is observed in a wide range of densities and couplings. The phenomenon originates in antiferromagnetic correlations ``across holes'' dynamically generated to improve hole movement, as it occurs in the one-dimensional Hubbard model and in recent studies of the two-dimensional extended t-J model. The close proximity of ferromagnetic and phase-separated states in parameter space are also discussed.

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Andre Luiz Malvezzi, Elbio Dagotto. 2001-03-20. Origin of Spin Incommensurability in Hole-doped S=1 $\rm Y_{2-x}Ca_x Ba Ni O_5$ Chains. https://doi.org/10.1103/physrevb.63.140409

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