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The influence of structure disorder on mean atomic momentum fluctuations and a spin-wave spectrum

I. Vakarchuk·V. Tkachuk·T. Kuliy
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Abstract

The relation between atomic momenta fluctuations and density fluctuations is obtained in frames of mean-field approximation. Using two-time temperature Green functions within Tyablikov approximation the equations for spin excitation energy and damping are obtained. The asymptotics of energy and damping in the long-wave limit are investigated and the anomalous behaviour of spin-wave stiffness constant is discussed.

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I. Vakarchuk, V. Tkachuk, T. Kuliy. 1995-02-10. The influence of structure disorder on mean atomic momentum fluctuations and a spin-wave spectrum. https://doi.org/10.1016/0304-8853(95)00004-6

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