Herein, the influence of Zn nonmagnetic doping on magnetic properties above the Curie temperature of La 1− x Dy x Mn 1− y Zn y O 3 diluted samples is studied. The Zn doping effect on the structure and distortions of MnO 6 octahedra are observed, suggesting a relaxation effect of the tilting on the stress introduced by Zn doping. Magnetization versus temperature shows a transition from paramagnetic (PM) to ferromagnetic (FM) phase in the temperature range from 130 to 190 K. In the PM regime, FM spin clusters are observed by dc susceptibility and electron PM resonance (EPR). The effective moment of the clusters is obtained from the high‐temperature dc susceptibility. The effective exchange constants, J , are estimated using an open‐source program for the high‐temperature expansion (HTE) for inverse susceptibility of the spin Heisenberg model.
Tópico:
Magnetic and transport properties of perovskites and related materials