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arXiv · 1608.05059

Quantum-critical spin dynamics in a Tomonaga-Luttinger liquid studied with muon-spin relaxation

J. S. Möller·T. Lancaster·S. J. Blundell·F. L. Pratt·P. J. Baker·F. Xiao·R. C. Williams·W. Hayes·M. M. Turnbull·C. P. Landee
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Abstract

We demonstrate that quantum-critical spin dynamics can be probed in high magnetic fields using muon-spin relaxation ($\mu^{+}$SR). Our model system is the strong-leg spin ladder bis(2,3-dimethylpyridinium) tetrabromocuprate (DIMPY). In the gapless Tomonaga-Luttinger liquid phase we observe finite-temperature scaling of the $\mu^{+}$SR $1/T_1$ relaxation rate which allows us to determine the Luttinger parameter $K$. We discuss the benefits and limitations of local probes compared with inelastic neutron scattering.

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J. S. Möller, T. Lancaster, S. J. Blundell, F. L. Pratt, P. J. Baker, F. Xiao, R. C. Williams, W. Hayes, M. M. Turnbull, C. P. Landee. 2016-08-17. Quantum-critical spin dynamics in a Tomonaga-Luttinger liquid studied with muon-spin relaxation. https://doi.org/10.1103/physrevb.95.020402

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