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arXiv · 0704.0604

Magnetism in the high-Tc analogue Cs2AgF4 studied with muon-spin relaxation

T. Lancaster·S. J. Blundell·P. J. Baker·W. Hayes·S. R. Giblin·S. E. McLain·F. L. Pratt·Z. Salman·E. A. Jacobs·J. F. C. Turner·T. Barnes
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Abstract

We present the results of a muon-spin relaxation study of the high-Tc analogue material Cs2AgF4. We find unambiguous evidence for magnetic order, intrinsic to the material, below T_C=13.95(3) K. The ratio of inter- to intraplane coupling is estimated to be |J'/J|=1.9 x 10^-2, while fits of the temperature dependence of the order parameter reveal a critical exponent beta=0.292(3), implying an intermediate character between pure two- and three- dimensional magnetism in the critical regime. Above T_C we observe a signal characteristic of dipolar interactions due to linear F-mu-F bonds, allowing the muon stopping sites in this compound to be characterized.

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T. Lancaster, S. J. Blundell, P. J. Baker, W. Hayes, S. R. Giblin, S. E. McLain, F. L. Pratt, Z. Salman, E. A. Jacobs, J. F. C. Turner, T. Barnes. 2007-04-04. Magnetism in the high-Tc analogue Cs2AgF4 studied with muon-spin relaxation. https://doi.org/10.1103/physrevb.75.220408

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