magnetism

Applications of magnetic core-shell particles

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.

Design of active magneto-optic elements

While macroscopic passive magneto-optic devices, such as polarization rotators, are common optical components used in a variety of experiments, nano-scale active magneto-optic elements are an important part of quantum information transport. Plasmon resonances (light induced collective electron oscillations) can be used to tailor the Kerr rotation and ellipticity in a broad range, up to controlled sign changes.

Collective magnetic properties of iron oxide nanoparticle-clusters

Block copolymers can be used as “containers” which can be filled, e.g., by drugs, dyes, nanoparticles etc. Such polymeric containers can also contain ordered clusters of nanoparticles – with possibly novel collective properties, different from those of single nanoparticles and bulk material.

In a recent study, FeO_x nanoparticles of diameter 8 nm were encapsulated in such a block copolymer with ratios of polymer:nanoparticle between 20:1 and 400:1. Additionally, hybrid nanomaterials combining FeO_x with quantum dots, quantum rods, gold nanoparticles etc. were produced.

The 2014 Magnetism Roadmap

The research field of magnetism ranges from daily-life applications to novel ideas and products, such as magnetic sensors, memory cells, or nanoparticles used for biomedicine. In such a broad field, it is often hard to keep track of the latest developments. All the better to have an actual roadmap, pointing out new research areas of special interest, written by specialists for this topic.