ESR investigations on Ca perovskite

Abstract

Electron spin resonance studies on fine powders of La 0.65 Ca 0.35 MnO 3 , performed in the X band, are reported. The coexistence of paramagnetic and ferromagnetic phases, in a narrow temperature range close to the Curie temperature, is observed. The electron spin resonance measurements do not support the presence of bipolarons above the Curie temperature. Temperature dependence of the ESR linewidth is governed by the hopping of polarons and the corresponding activation energy is about 150 meV above T C .

Neutron powder diffraction studies of the La0.65Pb0.35MnO3 perovskite

“…Therefore, the tilt angle values near T C are close to 90j. An additional confirmation of the spin reorientation transition, found from neutron diffraction measurements, has been obtained on La 0.65 Pb 0.35 MnO 3 thin films using ferromagnetic resonance (FMR) technique [9]. The temperature dependence of the angle U, representing the average orientation of the electronic spins in the plane of the film, is plotted in Fig.…”

“…Close to the Curie temperature, the Mn 3 + octahedra become locally JT active and the spins are canted at an average angle with respect to the c-axis corresponding to R3c structure. It is possible that the JT distortions prevail above the Curie temperature, as was recently investigated in FMR measurements [9]. It also known that larger dopant atoms, such as Sr and Pb, introduce a higher degree of disorder, and the system adopts a rhombohedral structure with apparently no JahnTeller distortions.…”

Structure and Magnetic Properties of Nanostructured Pd–Fe Thin Films Produced by Pulse Electrodeposition

“…6b) it is very probably that a phase with magnetization perpendicular to the film plane is present in the studied sample (see the magnetic hysteresis measurements below). The detailed analysis of the FMR measurements is under intensive development in the fashion of the works [6][7][8]. …”