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Spin stiffness and quantum fluctuations in C-type and A-type antiferromagnets

M. Raczkowski·A. M. Oles
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Abstract

We present a systematic study of quantum fluctuations in the C-type and A-type antiferromagnetic (AF) phases in cubic lattices and in bilayer systems. Using the linear spin-wave theory, we show that the spin stiffness and the quantum corrections to the order parameter and energy obtained for C-AF and A-AF phases decrease with the increasing number of ferromagnetic bonds. Therefore, the quantum spin effects in LaMnO_3 and in LaVO_3 are rather small, suggesting the magnetic moments of 3.91 and 1.89 Bohr's magneton, respectively. They cannot explain the strong reduction of the magnetic order parameter observed in cubic vanadates.

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M. Raczkowski, A. M. Oles. 2002-11-05. Spin stiffness and quantum fluctuations in C-type and A-type antiferromagnets. https://doi.org/10.1103/physrevb.66.094431

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