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Systematic Study of Magnetic Interactions in Insulating Cuprates

Yoshiaki Mizuno·Takami Tohyama·Sadamichi Maekawa
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Abstract

The magnetic interactions in one-dimensional, two-dimensional (2D) and ladder cuprates are evaluated systematically by using small Cu-O clusters. We find that the superexchange interaction J between nearest neighbor Cu spins strongly depends on Cu-O structure through the Madelung potential, and in 2D and ladder cuprates there is a four-spin interaction Jcyc, with magnitude of 10% of J. We show that Jcyc has a strong influence on the magnetic excitation in the high-energy region of 2D cuprates.

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Yoshiaki Mizuno, Takami Tohyama, Sadamichi Maekawa. 2000-04-28. Systematic Study of Magnetic Interactions in Insulating Cuprates. https://doi.org/10.1016/s0921-4534(00)00549-9

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