Indications of phase separation in polycrystalline La1ÀxSrxMnO3 for xÉ0.5
نویسندگان
چکیده
We present systematic studies of polycrystalline La12xSrxMnO3 where x is varied from 0.46 to 0.53 at 0.01 intervals. We have measured the magnetic resonance, ac susceptibility, dc magnetization, x-ray diffraction, four-probe resistivity, and optical reflectivity. The data seem to indicate that, at low T, the materials are intimate mixtures of ferromagnetic and antiferromagnetic microregions. For x.0.48 we observe anomalies pointing toward charge ordering on lowering T. An effective-medium theory is presented, and an appropriate phase diagram is proposed.
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