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Antiferromagnetism in doped anisotropic two-dimensional spin-Peierls systems

A. Dobry·P. Hansen·J. Riera·D. Augier·D. Poilblanc
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Abstract

We study the formation of antiferromagnetic correlations induced by impurity doping in anisotropic two-dimensional spin-Peierls systems. Using a mean-field approximation to deal with the inter-chain magnetic coupling, the intra-chain correlations are treated exactly by numerical techniques. The magnetic coupling between impurities is computed for both adiabatic and dynamical lattices and is shown to have an alternating sign as a function of the impurity-impurity distance, hence suppressing magnetic frustration. An effective model based on our numerical results supports the coexistence of antiferromagnetism and dimerization in this system.

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A. Dobry, P. Hansen, J. Riera, D. Augier, D. Poilblanc. 1999-05-21. Antiferromagnetism in doped anisotropic two-dimensional spin-Peierls systems. https://doi.org/10.1103/physrevb.60.4065

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