Magnetic properties of (La<inf>0.7</inf>Sr<inf>0.3</inf>MnO<inf>3</inf>)<inf>x</inf>(CaCu<inf>3</inf>Ti<inf>4</inf>O<inf>12</inf>)<inf>1−x</inf>nanostructured composites

Abstract

© 2017 Elsevier B.V. (La 0.7 Sr 0.3 MnO 3 ) x (CaCu 3 Ti 4 O 12 ) 1−x (0.01 ≤ x ≤ 0.3) nanostructured composites with La 0.7 Sr 0.3 MnO 3 (LSMO) microinclusions in CaCu 3 Ti 4 O 12 (CCTO) matrix were synthesized using a solid state method. The structural and microstructural details were studied by X-ray diffraction (XRD), X-ray fluorescence (XFA), scaning electron microscope (SEM) and transmission electron microscope (TEM) techniques. The magnetic properties were studied by electron spin resonance (ESR) and magnetometry methods. In the concentration range 0.01 < x < 0.1 physical properties of composites differ from the properties of the individual components CCTO or LSMO. The Curie temperature of the ferromagnetic phase for all concentrations is T C = 315 K, that is less at 50 K than in pure LSMO. The Weiss constant of the paramagnetic phase has the strong concentration dependance. The observed mutual influence on the magnetic properties of both components can be tentatively attributed to the interface exchange interactions between them, hinting a possible magnetic proximity effect.