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Magnon Bose condensation in symmetry breaking magnetic field

S. V. Maleyev·V. P. Plakhty·S. V. Grigoriev·A. I. Okorokov·A. V. Syromyatnikov
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Abstract

Magnon Bose condensation (BC)in the symmetry breaking magnetic field is a result of unusual form of the Zeeman energy, which has terms linear in the spin-wave operators and terms mixing excitations differ in the Wave-vector of the magnetic structure. The following examples are considered: simple easy-plane tetragonal antiferromagnets (AF), frustrated AF family$R_2Cu O_4$ where $R=Pr,Nd$ etc. and cubic magnets with the Dzyaloshinskii-Moriya interaction ($Mn Si$ etc.). In all cases the BC becomes important when the magnetic field becomes comparable with the spin-wave gap. The theory is illustrated by existing experimental results.

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S. V. Maleyev, V. P. Plakhty, S. V. Grigoriev, A. I. Okorokov, A. V. Syromyatnikov. 2006-09-01. Magnon Bose condensation in symmetry breaking magnetic field. https://doi.org/10.1088/0953-8984%2F19%2F14%2F145208

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