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Modified spin-wave description of the nuclear spin relaxation in ferrimagnetic Heisenberg chains

Shoji Yamamoto
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Abstract

We make a modified spin-wave description of the nuclear spin relaxation in Heisenberg alternating-spin chains with antiferromagnetic exchange coupling. In contrast with the conventional one-dimensional antiferromagnetic spin-wave theory, which is plagued with the divergence of the sublattice magnetization even in the ground state, the present spin-wave description is highly successful over a wide temperature range. The temperature dependence of the relaxation rate $T_1^{-1}$ significantly varies with the crystalline structure, exhibiting both ferromagnetic and antiferromagnetic aspects. $T_1^{-1}$ further shows a unique dependence on the applied field, which turns out an indirect observation of the quadratic dispersion relations.

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Shoji Yamamoto. 2000-04-18. Modified spin-wave description of the nuclear spin relaxation in ferrimagnetic Heisenberg chains. https://doi.org/10.1143/jpsj.69.2324

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