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arXiv · 1302.4867

Lifetimes of antiferromagnetic magnons in two and three dimensions: experiment, theory, and numerics

S. P. Bayrakci·D. A. Tennant·Ph. Leininger·T. Keller·M. C. R. Gibson·S. D. Wilson·R. J. Birgeneau·B. Keimer
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Abstract

A high-resolution neutron spectroscopic technique is used to measure momentum-resolved magnon lifetimes in the prototypical two- and three-dimensional antiferromagnets Rb2MnF4 and MnF2, over the full Brillouin zone and a wide range of temperatures. We rederived theories of the lifetime resulting from magnon-magnon scattering, thereby broadening their applicability beyond asymptotically small regions of wavevector and temperature. Corresponding computations, combined with a small contribution reflecting collisions with domain boundaries, yield excellent quantitative agreement with the data.

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S. P. Bayrakci, D. A. Tennant, Ph. Leininger, T. Keller, M. C. R. Gibson, S. D. Wilson, R. J. Birgeneau, B. Keimer. 2013-02-20. Lifetimes of antiferromagnetic magnons in two and three dimensions: experiment, theory, and numerics. https://doi.org/10.1103/physrevlett.111.017204

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