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Thermodynamic properties of the field-induced Neel order of TlCuCl3

S. Stark·O. Heyer·A. Vasiliev·A. Oosawa·H. Tanaka·T. Lorenz
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Abstract

TlCuCl3 shows a quantum phase transition from a spin-gap phase to a Neel-ordered ground state as a function of magnetic field around H_{C0}~4.8T. From measurements of the specific heat c and the linear thermal expansion alpha_i we calculate the Grueneisen parameter Gamma_i(T)=alpha_i/c. Close to H_{C0} we find a diverging Gamma_i(T->0, in qualitative agreement with theoretical predictions. However, the predicted individual temperature dependencies of alpha(T) and c(T) are not reproduced by our experimental data.

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S. Stark, O. Heyer, A. Vasiliev, A. Oosawa, H. Tanaka, T. Lorenz. 2006-10-17. Thermodynamic properties of the field-induced Neel order of TlCuCl3. https://doi.org/10.1016/j.jmmm.2006.10.464

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