Core-shell particles can be created, e.g., as hard magnetic shell and soft magnetic core or vice versa. Due to the progress in controlling the particle properties during synthesis and in characterizing the shape and magnetic properties, such bi-magnetic structures can nowadays be utilized for a variety of different applications, e.g. in magnetic recording, magneto-transport, biomedicine, or microwave absorption. Although not all properties are fully understood and controllable yet, such core-shell particles offer great potential for future applications.
The authors of this review paper give a broad overview of different possibilities and detailed information about magnetic and other properties of bi-magnetic core-shell particles, resulting in a comprehensive base for future research on such particles.
Alberto López-Ortega, Marta Estrader, German Salazar-Alvarez, Alejando G. Roca, Josep Nogués
Applications of exchange coupled bi-magnetic hard/soft and soft/hard magnetic core/shell nanoparticles
Physics Reports 553, 1-32 (2015)