Strong Electrical-Magnetic Correlation in Pr0.7Sr0.25MnO3 Lacunar Manganite

We have investigated in this work the presence of a possible correlation between electrical and magnetic properties in Pr0.7Sr0.25MnO3 lacunar compound synthesized by solid-state reaction. The temperature dependence of electrical resistivity ρ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\rho$$\end{document}(T) shows a metal–insulator transition at Tρ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${T}_{\rho }$$\end{document} = 207 K. The phenomenological percolation model, based on the segregation of ferromagnetic metallic phases and paramagnetic insulating regions, was successfully used in order to fit the electrical resistivity in the vicinity of the electrical transition temperature. The studied sample exhibits a strong correlation between electrical and magnetic properties. Such correlation was exploited to evaluate the evolution of temperature dependent magnetic entropy change from the isothermal resistivity measurements. The percolative nature of the electrical/magnetic transition can be a possible origin of the colossal magnetoresistive effect observed near Tρ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${T}_{\rho }$$\end{document}.