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Realization of Bose-Einstein condensation of dilute magnons in TlCuCl$_3$

T. Nikuni·M. Oshikawa·A. Oosawa·H. Tanaka
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Abstract

The recent observation [Oosawa et al. J. Phys. : Condens. Matter {\bf 11}, 265 (1999)] of the field-induced Néel ordering in a spin-gap magnetic compound TlCuCl$_3$ is interpreted as a Bose-Einstein Condensation of magnons. A mean-field calculation based on this picture is shown to describe well the temperature dependence of the magnetization. The present system opens a new area for studying Bose-Einstein condensation of thermodynamically large number of particles in a grand-canonical ensemble.

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T. Nikuni, M. Oshikawa, A. Oosawa, H. Tanaka. 1999-08-09. Realization of Bose-Einstein condensation of dilute magnons in TlCuCl$_3$. https://doi.org/10.1103/physrevlett.84.5868

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