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Magnetic Interaction in Insulating Cuprates

Yoshiaki Mizuno·Takami Tohyama·Sadamichi Maekawa
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Abstract

We examine two-spin (2S) and cyclic four-spin (4S) magnetic interactions in insulating ladder and two-dimensional (2D) cuprates. By a comparison of eigenstates between d-p and Heisenberg models, we evaluate magnitudes of these interactions. We find that the 4S interaction is $\sim$10% of nearest neighboring 2S interaction, and a diagonal 2S interaction is considerably small. The 4S interaction for a ladder cuprate is larger than that for 2D one, and plays an important role in the low-energy excitation. The Heisenberg ladder with the obtained 2S and 4S interactions reproduces very well the experimental result of the temperature dependence of the magnetic susceptibility.

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Yoshiaki Mizuno, Takami Tohyama, Sadamichi Maekawa. 1999-10-05. Magnetic Interaction in Insulating Cuprates. https://arxiv.org/abs/cond-mat/9906444

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