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Nuclear spin relaxation in ordered bimetallic chain compounds

Shoji Yamamoto
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Abstract

A theoretical interpretation is given to recent proton spin relaxation-time (T_1) measurements on NiCu(C_7H_6N_2O_6)(H_2O)_3$\cdot$2H_2O, which is an ideal one-dimensional ferrimagnetic Heisenberg model system of alternating spins 1 and 1/2. The relaxation rate T_1^{-1} is formulated in temrs of the spin-wave theory and is evaluated by the use of a quantum Monte Carlo method. Calculations of the temperature and applied-field (H) dependences of T_1^{-1} are in total agreement with the experimental findings. T_1 behaves as $T_1^{-1}\propto H^{-1/2}$, which turns out an indirect observation of the quadratic dispersion relations dominating the low-energy physics of quantum ferrimagnets.

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Shoji Yamamoto. 1999-12-18. Nuclear spin relaxation in ordered bimetallic chain compounds. https://doi.org/10.1016/s0375-9601(99)00858-0

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