Electronic and magnetic instability in Pr0.65Ca0.25Sr0.1MnO3

Abstract Electronic and magnetic instability in polycrystalline Pr 0.65 Ca 0.25 Sr 0.1 MnO 3 manganite has been established from a systematic study of resistivity ( ρ ), magnetization ( M ) and specific heat ( C ). The sample shows a charge ordering transition at T CO ∼200 K, an antiferromagnetic (AFM) ordering transition at T N ∼175 K, a metal–insulator (MI) transition at T MI ∼80 K and an unusual magnetic ordering transition at T M * ∼45 K in the absence of magnetic fields. Though the C data do not show any anomaly at T MI for MI transition, these illustrate a much smaller anomaly than expected one at T M * and is suppressed by magnetic fields. This indicates that the unusual magnetic ordering in this sample is of canted, fluctuated or phase separation of AFM and ferromagnetic in nature which is established from the T – H phase diagram, as well as the thermal and magnetic hysteresis in ρ , M and C .