Role of A site and B site ion substitutions on the low-temperature magnetic behaviour of Ca2Fe2O5

Abstract

In the present paper, we report the structural and low-temperature magnetic properties of Sm-substituted Ca2Fe2O5 (Ca2(1-x)Sm2xFe2O5, x = 0.05, 0.1) and Co-substituted Ca2Fe2O5( Ca2Fe2(1-y)Co2yO5, y = 0.1, 0.2). The polycrystalline samples of Sm and Co-based compounds, synthesised by a solid-state reaction route, are found to be crystallised with space group Icmm and Pnma respectively. The gradual substitution/doping of Sm3+ (5 % and 10 %) replacing Ca shows a significant change in temperature dependant magnetic behaviour, assumed to originate from complex interactions of Sm and Fe ions. For Co-substituted samples, the magnetic study as a function of temperature suggests the signature of ferri/ferromagnetic interactions along with the probable signature of a glassy feature. Isothermal magnetisation characterisations indicate the pure antiferromagnetic interactions in Sm samples, whereas the onset of hysteresis in Co samples can be correlated with the ferri/ferromagnetic nature of samples with the antiferromagnetic ground state.