A pr 1 99 9 Spin - wave contributions to nuclear magnetic relaxation in magnetic metals
نویسنده
چکیده
The longitudinal and transverse nuclear magnetic relaxation rates 1/T1(T ) and 1/T2(T ) are calculated for threeand two-dimensional (3D and 2D) metallic ferroand antiferromagnets (FM and AFM) with localized magnetic moments in the spin-wave temperature region. The contribution of the onemagnon decay processes is strongly enhanced in comparison with the standard T -linear Korringa term, especially for the FM case, and diverges logarithmically for the 3D AFM case and as ω 0 for the 2D AFM case, the divergence being cut at the magnon gap ω0 due to magnetic anisotropy. The electronmagnon scattering processes yield T 2 ln(T/ω0) and T 2/ω 1/2 0 -terms in 1/T1 for the 3D AFM and 2D FM cases, respectively. The two-magnon (“Raman”) contributions are investigated and demonstrated to be large in the 2D FM case. Peculiarities of the isotropic 2D limit are analyzed. Typeset using REVTEX 1
منابع مشابه
D ec 1 99 9 Spin - wave contributions to nuclear magnetic relaxation in magnetic metals
The longitudinal and transverse nuclear magnetic relaxation rates 1/T1(T ) and 1/T2(T ) are calculated for threeand two-dimensional (3D and 2D) metallic ferroand antiferromagnets (FM and AFM) with localized magnetic moments in the spin-wave temperature region. The contribution of the onemagnon decay processes is strongly enhanced in comparison with the standard T -linear Korringa term, especial...
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