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arXiv · 0808.2715

Thermodynamics of the Spin Luttinger-Liquid in a Model Ladder Material

Ch. Rüegg·K. Kiefer·B. Thielemann·D. F. McMorrow·V. Zapf·B. Normand·M. B. Zvonarev·P. Bouillot·C. Kollath·T. Giamarchi·S. Capponi·D. Poilblanc·D. Biner·K. W. Krämer
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Abstract

The phase diagram in temperature and magnetic field of the metal-organic, two-leg, spin-ladder compound (C5H12N)2CuBr4 is studied by measurements of the specific heat and the magnetocaloric effect. We demonstrate the presence of an extended spin Luttinger-liquid phase between two field-induced quantum critical points and over a broad range of temperature. Based on an ideal spin-ladder Hamiltonian, comprehensive numerical modelling of the ladder specific heat yields excellent quantitative agreement with the experimental data across the complete phase diagram.

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Ch. Rüegg, K. Kiefer, B. Thielemann, D. F. McMorrow, V. Zapf, B. Normand, M. B. Zvonarev, P. Bouillot, C. Kollath, T. Giamarchi, S. Capponi, D. Poilblanc, D. Biner, K. W. Krämer. 2008-10-31. Thermodynamics of the Spin Luttinger-Liquid in a Model Ladder Material. https://doi.org/10.1103/physrevlett.101.247202

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