Inhomogeneous magnetic clusters above the Curie point in Nd 0.5Ca xSr 0.5− xMnO 3 ( x = 0.1 and 0.3)

Abstract

The presence of inhomogeneous magnetic clusters in Nd 0.5Ca x Sr 0.5− x MnO 3 ( x = 0.1 and 0.3) system has been investigated by dc magnetic susceptibility, magnetoresistance (MR) and ESR studies. The nature of magnetic transitions is found to be of second order in x = 0.1 and is of first order in case of x = 0.3 composition. The ferromagnetic clusters in the paramagnetic region show the signature of Griffiths-like phase for the x = 0.1 sample. The onset of predominant charge-ordered antiferromagnetic correlations above T C results in the deviation from Curie–Weiss law as an upturn in the magnetic susceptibility of x = 0.3 sample. The competition between the FM/AFM interactions arising from A-site cation disorder leads to quenched disorder in this system.