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arXiv · 0803.2016

Magnetic states and spin-glass properties in Bi0.67Ca0.33MnO3: macroscopic ac measurements and neutron scattering

M. Giot·A. Pautrat·G. Andre·D. Saurel·M. Hervieu·J. Rodriguez-Carvajal
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Abstract

We report on the magnetic properties of the manganite Bi_{1-x}Ca_{x}MnO_3 (x=0.33) at low temperature. The analysis of the field expansion of the ac susceptibility and the observation of aging properties make clear that a spin glass phase appears below T = 39K, in the presence of magnetic order. Neutron scattering shows both magnetic Bragg scattering and magnetic diffusion at small angles, and confirms this coexistence. In contrast to Pr_{1-x}Ca_{x}MnO_3 (x=0.3-0.33) which exhibits a mesoscopic phase separation responsible for a field driven percolation, the glassy and short range ferromagnetic order observed here does not cause colossal magnetoresistance (CMR).

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M. Giot, A. Pautrat, G. Andre, D. Saurel, M. Hervieu, J. Rodriguez-Carvajal. 2008-03-13. Magnetic states and spin-glass properties in Bi0.67Ca0.33MnO3: macroscopic ac measurements and neutron scattering. https://doi.org/10.1103/physrevb.77.134445

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