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arXiv · 0804.2639

Controlling Luttinger liquid physics in spin ladders under a magnetic field

M. Klanjsek·H. Mayaffre·C. Berthier·M. Horvatic·B. Chiari·O. Piovesana·P. Bouillot·C. Kollath·E. Orignac·R. Citro·T. Giamarchi
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Abstract

We present a 14N nuclear magnetic resonance study of a single crystal of CuBr4(C5H12N)2 (BPCB) consisting of weakly coupled spin-1/2 Heisenberg antiferromagnetic ladders. Treating ladders in the gapless phase as Luttinger liquids, we are able to fully account for (i) the magnetic field dependence of the nuclear spin-lattice relaxation rate 1/T_1 at 250 mK and for (ii) the phase transition to a 3D ordered phase occuring below 110 mK due to weak interladder exchange coupling. BPCB is thus an excellent model system where the possibility to control Luttinger liquid parameters in a continuous manner is demonstrated and Luttinger liquid model tested in detail over the whole fermion band.

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M. Klanjsek, H. Mayaffre, C. Berthier, M. Horvatic, B. Chiari, O. Piovesana, P. Bouillot, C. Kollath, E. Orignac, R. Citro, T. Giamarchi. 2008-09-29. Controlling Luttinger liquid physics in spin ladders under a magnetic field. https://doi.org/10.1103/physrevlett.101.137207

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