Effects on magnetocaloric and magnetoresistive properties due to nonmagnetic Zn2+ substitution at Mn-site in charge-ordered Pr0.5Ca0.5MnO3 manganite.

This study of nonmagnetic Zn-substitution effect on the charge-ordered behavior of Pr 0.5 Ca 0.5 Mn 1- x Zn x O 3 (x = 0.0, 0.1) compounds reveal the weakening of strong charge-ordered antiferromagnetic state of the parent compound (x = 0.0). Magnetocaloric effect (MCE) has been calculated using a Python package from isothermal M-H data for these samples. A prominent ferromagnetic contribution in the antiferromagnetic matrix for Mn-site doping is observed, which removes the inverse MCE observed in the pristine sample below the charge ordering temperature T CO. Development of ferromagnetism in the doped system exhibits a metal-insulator transition at T MI = 90 K under 7 T magnetic field and large magnetoresistance (> 99 %), which is not observed in parent compound. Magnetic field-dependent hysteresis at low temperature reveals the ferromagnetic metastability and first-order nature of magnetic phase transition. Random occupation of Zn at the Mn-site of the parent compound disrupts 1:1 Mn3+/Mn4+ charge-ordered superstructure of the parent compound which weakens the charge-ordered antiferromagnetic strength promoting ferromagnetism and double-exchange interaction through an enhanced 2 p -3 d hybridization between Mn and O ions. [Display omitted] • Substitution of Zn in Pr0.5Ca0.5Mn1-xZnxO3 compounds affects their charge-ordered behavior. • Strong charge-ordered antiferromagnetic state in the parent compound weakens with Zn substitution. • MCE was calculated using a Python package from isothermal M-H data. • Mn-site doping removes the inverse MCE observed in the parent sample below the charge ordering temperature. • Metal-insulator transition at TMI = 90 K under a 7 T magnetic field and large magnetoresistance (> 99 %) is observed. [ABSTRACT FROM AUTHOR]