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arXiv · 1307.0103

Attractive Tomonaga-Luttinger Liquid in a Quantum Spin Ladder

M. Jeong·H. Mayaffre·C. Berthier·D. Schmidiger·A. Zheludev·M. Horvatić
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Abstract

We present NMR measurements of a strong-leg spin-1/2 Heisenberg antiferromagnetic ladder compound (C7H10N)2CuBr4 under magnetic fields up to 15 T in the temperature range from 1.2 K down to 50 mK. From the splitting of NMR lines we determine the phase boundary and the order parameter of the low-temperature (3-dimensional) long-range-ordered phase. In the Tomonaga-Luttinger regime above the ordered phase, NMR relaxation reflects characteristic power-law decay of spin correlation functions as 1/T1 T^(1/2K-1), which allows us to determine the interaction parameter K as a function of field. We find that field-dependent K varies within the 1<K<2 range which signifies attractive interaction between the spinless fermions in the Tomonaga-Luttinger liquid.

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M. Jeong, H. Mayaffre, C. Berthier, D. Schmidiger, A. Zheludev, M. Horvatić. 2013-06-29. Attractive Tomonaga-Luttinger Liquid in a Quantum Spin Ladder. https://doi.org/10.1103/physrevlett.111.106404

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