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Spin freezing and magnetic inhomogeneities in bilayer manganites

A. I. Coldea·S. J. Blundell·C. A. Steer·J. F. Mitchell·F. L. Pratt
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Abstract

We have performed a muon spin rotation study on polycrystalline samples of electron-doped layered manganites, La$_{2-2x}$Sr$_{1+2x}$Mn$_2$O$_7$ (0.4< x<1), in order to investigate the local magnetic structure and spin dynamics. Our results provide evidence for phase separation into A-type antiferromagnetic and charge-ordered phases for x=0.52 and spin freezing at low temperatures (T<100K) for 0.52<x<0.75. A new phase diagram which includes this spin freezing region is proposed.

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A. I. Coldea, S. J. Blundell, C. A. Steer, J. F. Mitchell, F. L. Pratt. 2003-01-13. Spin freezing and magnetic inhomogeneities in bilayer manganites. https://arxiv.org/abs/cond-mat/0301177

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