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arXiv · 1203.1161

Persistent dynamics in the S=1/2 quasi-one-dimensional chain compound Rb4Cu(MoO4)3 probed with muon-spin relaxation

T. Lancaster·P. J. Baker·F. L. Pratt·S. J. Blundell·W. Hayes·D. Prabhakaran
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Abstract

We report the results of muon-spin relaxation measurements on the low-dimensional antiferromagnet Rb4Cu(MoO4)3. No long-range magnetic order is observed down to 50 mK implying a ratio T_N/J<0.005 (where J is the principal exchange strength along the spin chains) and an effective ratio of interchain to intrachain exchange of |J_perp/J|<2 x 10^-3, making the material an excellent realization of a one-dimensional quantum Heisenberg antiferromagnet. We probe the persistent spin excitations at low temperatures and find that ballistic spin transport dominates the excitations detected below 0.3 K.

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T. Lancaster, P. J. Baker, F. L. Pratt, S. J. Blundell, W. Hayes, D. Prabhakaran. 2012-03-06. Persistent dynamics in the S=1/2 quasi-one-dimensional chain compound Rb4Cu(MoO4)3 probed with muon-spin relaxation. https://doi.org/10.1103/physrevb.85.184404

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