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arXiv · 1302.6905

Weak magnetic transitions in pyrochlore Bi2Ir2O7

P. J. Baker·J. S. Moeller·F. L. Pratt·W. Hayes·S. J. Blundell·T. Lancaster·T. F. Qi·G. Cao
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Abstract

Muon spin relaxation measurements on Bi2Ir2O7 show that it undergoes a bulk magnetic transition at 1.84(3) K. This is accompanied by increases in the muon spin relaxation rate and the amplitude of the non-relaxing part of the signal. The magnetic field experienced by muons is estimated to be 0.7 mT at low-temperature, around two orders of magnitude smaller than that in other pyrochlore iridates. These results suggest that the low-temperature state represents ordering of exceptionally small magnetic moments with persistent weak dynamics. The relaxation rate increases further below 0.23(4) K, coincident with a growth in the specific heat, suggesting the existence of a second low-temperature magnetic transition.

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P. J. Baker, J. S. Moeller, F. L. Pratt, W. Hayes, S. J. Blundell, T. Lancaster, T. F. Qi, G. Cao. 2013-02-27. Weak magnetic transitions in pyrochlore Bi2Ir2O7. https://doi.org/10.1103/physrevb.87.180409

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