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Observation of Field-Induced Transverse Néel Ordering in the Spin Gap System TlCuCl$_3$

H. Tanaka·A. Oosawa·T. Kato·H. Uekusa·Y. Ohashi·K. Kakurai·A. Hoser
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Abstract

Neutron elastic scattering experiments have been performed on the spin gap system TlCuCl$_3$ in magnetic fields parallel to the $b$-axis. The magnetic Bragg peaks which indicate the field-induced Néel ordering were observed for magnetic field higher than the gap field $H_{\rm g}\approx 5.5$ T at $Q=(h, 0, l)$ with odd $l$ in the $a^*-c^*$ plane. The spin structure in the ordered phase was determined. The temperature and field dependence of the Bragg peak intensities and the phase boundary obtained were discussed in connection with a recent theory which describes the field-induced Néel ordering as a Bose-Einstein condensation of magnons.

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H. Tanaka, A. Oosawa, T. Kato, H. Uekusa, Y. Ohashi, K. Kakurai, A. Hoser. 2001-01-19. Observation of Field-Induced Transverse Néel Ordering in the Spin Gap System TlCuCl$_3$. https://doi.org/10.1143/jpsj.70.939

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