Study of magnetic and magnetotransport properties in polycrystalline Pr0.6A′0.2Sr0.2MnO3 (A′ ≡ Y, La) compounds: Observation of enhanced electron–electron interaction

Abstract A comparative study of magnetic, electrical, and magnetotransport properties for the polycrystalline bulk Pr0.6A′0.2Sr0.2MnO3 (A′ ≡ Y, La) compounds has been presented in this article. The aforementioned ABO3 type perovskite compounds have been prepared with considering the average A-site ionic radius ( 〈 r A 〉 ) located around the phase boundary of the ferromagnetic insulator to ferromagnetic metal ground states of the prepared phase diagram for R0.8AE0.2MnO3 (R ≡ trivalent rare earth cations, AE ≡ divalent cations) compounds as a function of 〈 r A 〉 . The decrease in chemical disorder along with an increase in electronic bandwidth from Y to La doping increases the ferromagnetic transition temperature from 90 K to 175 K, respectively, and also suppresses the resistivity as well as magnetoresistance substantially. The temperature-dependent resistivity curves exhibit the metal–insulator like transitions around 100 K and 200 K for the doping with Y and La, respectively. Moreover, a resistivity minimum at low temperature is also observed for both systems. This behavior is best explained using a model, developed considering the presence of electron–electron elastic scattering or interaction at low temperatures. However, the Y doping system exhibits stronger electron–electron interaction compared to the La doping system, since the previous one accommodates a higher chemical disorder and lower electronic bandwidth.