Magnetic-field induced quantum phase transition and critical behavior in a gapped spin system TlCuCl3

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:310

Article; Proceedings Paper

Yamada, F. ; Ono, T. ; Fujisawa, M. ; Tanaka, H. ; Sakakibara, T.

关键词: TlCuCl3;    spin gap;    field-induced magnetic ordering;    magnon;    Bose-Einstein condensation;   

DOI  :  10.1016/j.jmmm.2006.10.372

来源: Elsevier

【 摘 要 】

Magnetization measurements were performed on TlCuCl3 with gapped ground state. The critical density and the magnetic phase diagram were obtained. The interacting constant was obtained as U/k(B) = 313 K. The experimental phase boundary for T < 5 K agrees perfectly with the magnon BEC theory based on the Hartree-Fock approximation with realistic dispersion relations and U/k(B) 320 K. 3 The exponent phi obtained with all the data points for T < 5 K is phi = 1.99, which is somewhat larger than theoretical exponent phi(BEC) = 3/2. However, it was found that the exponent converges at phi(BEC) =3/2 with decreasing fitting window. (c) 2006 Elsevier B.V. All rights reserved.

【 授权许可】

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