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Series of Bulk Magnetic Phase Transitions in NaxCoO2: a muSR study

P. Mendels·D. Bono·J. Bobroff·G. Collin·D. Colson·N. Blanchard·H. Alloul·I. Mukhamedshin·F. Bert·A. Amato·A. D. Hillier
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Abstract

Using muon spin rotation, well-defined bulk ~ 100% magnetic phases in NaxCoO2 are revealed. A novel magnetic phase is detected for x = 0.85 with the highest transition temperature ever observed for x >= 0.75. This stresses the diversity of x >=0.75 magnetic phases and the link between magnetic and structural degrees of freedom. For the charge-ordered x = 0.50 compound, a cascade of transitions is observed below 85 K. From a detailed analysis of our data, we conclude that the ordered moment varies continuously with temperature and suggest that the two secondary transitions at 48 K and 29 K correspond to a moderate reorientation of antiferromagnetically coupled moments.

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P. Mendels, D. Bono, J. Bobroff, G. Collin, D. Colson, N. Blanchard, H. Alloul, I. Mukhamedshin, F. Bert, A. Amato, A. D. Hillier. 2005-01-10. Series of Bulk Magnetic Phase Transitions in NaxCoO2: a muSR study. https://doi.org/10.1103/physrevlett.94.136403

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