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arXiv · 1008.3922

Field-induced Tomonaga-Luttinger liquid phase of a two-leg spin-1/2 ladder with strong leg interactions

Tao Hong·Y. H. Kim·C. Hotta·Y. Takano·G. Tremelling·M. M. Turnbull·C. P. Landee·H. -J. Kang·N. B. Christensen·K. Lefmann·K. P. Schmidt·G. S. Uhrig·C. Broholm
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Abstract

We study the magnetic-field-induced quantum phase transition from a gapped quantum phase that has no magnetic long-range order into a gapless phase in the spin-1/2 ladder compound bis(2,3-dimethylpyridinium) tetrabromocuprate (DIMPY). At temperatures below about 1 K, the specific heat in the gapless phase attains an asymptotic linear temperature dependence, characteristic of a Tomonaga-Luttinger liquid. Inelastic neutron scattering and the specific heat measurements in both phases are in good agreement with theoretical calculations, demonstrating that DIMPY is the first model material for an S=1/2 two-leg spin ladder in the strong-leg regime.

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Tao Hong, Y. H. Kim, C. Hotta, Y. Takano, G. Tremelling, M. M. Turnbull, C. P. Landee, H. -J. Kang, N. B. Christensen, K. Lefmann, K. P. Schmidt, G. S. Uhrig, C. Broholm. 2010-08-27. Field-induced Tomonaga-Luttinger liquid phase of a two-leg spin-1/2 ladder with strong leg interactions. https://doi.org/10.1103/physrevlett.105.137207

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