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arXiv · 0711.1574

Stability of Bose Einstein condensates of hot magnons in YIG

I. S. Tupitsyn·P. C. E. Stamp·A. L. Burin
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Abstract

We investigate the stability of the recently discovered room temperature Bose-Einstein condensate (BEC) of magnons in Ytrrium Iron Garnet (YIG) films. We show that magnon-magnon interactions depend strongly on the external field orientation, and that the BEC in current experiments is actually metastable - it only survives because of finite size effects, and because the BEC density is very low. On the other hand a strong field applied perpendicular to the sample plane leads to a repulsive magnon-magnon interaction; we predict that a high-density magnon BEC can then be formed in this perpendicular field geometry.

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I. S. Tupitsyn, P. C. E. Stamp, A. L. Burin. 2007-11-10. Stability of Bose Einstein condensates of hot magnons in YIG. https://doi.org/10.1103/physrevlett.100.257202

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