Direct Evidence of a Graded Magnetic Interface in Bimagnetic Core/Shell Nanoparticles Using Electron Magnetic Circular Dichroism (EMCD)
Daniel del-Pozo-Bueno, M. Varela, Marta Estrader, Alberto López‐Ortega, Alejandro G. Roca, J. Nogués, F. Peiró, Sònia Estradé
Abstract
shell. The EMCD measurements show that the nanoparticles are composed of four different zones with distinct magnetic moment in a concentric, onion-type, structure. These magnetic areas correlate spatially with the oxidation and composition gradient with the magnetic moment being largest at the surface and decreasing toward the core. The results show that the combination of EELS compositional mapping and EMCD can provide very valuable information on the inner magnetic structure and its correlation to the microstructure of magnetic nanoparticles.
Topics & Concepts
Magnetic circular dichroismMaterials scienceFerrimagnetismMagnetic nanoparticlesMagnetic momentNanoparticleMagnetic coreCore (optical fiber)Shell (structure)ElectronChemical physicsElectron energy loss spectroscopyMagnetizationMagnetometerInner coreAntiferromagnetismCondensed matter physicsNuclear magnetic resonanceNanotechnologyTransmission electron microscopyMagnetic fieldChemistryComposite materialPhysicsSpectral lineElectromagnetic coilQuantum mechanicsAstronomyIron oxide chemistry and applicationsMagnetic Properties and Synthesis of FerritesMagnetic properties of thin films