Electrical and magnetic properties of electron doped Bi _xCa_1−xMnO₃ (0<x≤0.33) ceramics

Abstract

Measurements of crystal structures, electrical and magnetic properties for the electron doped Bi _xCa_1−xMnO₃ (0<x≤0.33) reveal the presence of a variety of notable changes in correlation with magnetic transitions and charge ordering. Samples with x<0.2 in general show a clear ferromagnetic transitions around 130 K. On the other hand, samples with 0.2≤x≤0.33 show much more complex low-temperature magnetic properties perhaps due to the coupling between the magnetic states and orbital/charge ordering. Structural transformations and structural modulations in the x=0.25 and 0.33 samples have been observed by transmission electron microscopy.

Keywords

Bi _xCa_1−xMnO₃ / phase transition / charge ordering

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