Microscale magnetic compasses
- Author(s)
- Hidetsugu Shiozawa, Desai Zhang, Michael Eisterer, Paola Ayala, Thomas Pichler, Martha R. McCartney, David J. Smith
- Abstract
Microscale magnetic compasses have been synthesized with high yield. These ferromagnetic iron carbide nano-particles, which are encapsulated in a pair of parallel carbon needles, change their orientation in response to an external magnetic field. Electron holography reveals magnetic fields confined to the vicinity of the bicone-shaped particles, which are composed of only a few ferromagnetic domains. Aligned magnetically and encapsulated in an acrylate polymer matrix, these micro-compasses exhibit anisotropic bulk magnetic permeability with an easy axis normal to the needle direction that can be understood as a result of the anisotropic demagnetizing field of a non-spherical single-domain particle. This novel type of material with orthogonal magnetic and structural axes could be highly useful as magnetic components in electromagnetic wave absorbent materials and magnetorheological fluids.
- Organisation(s)
- Electronic Properties of Materials
- External organisation(s)
- Arizona State University, Technische Universität Wien, Czech Academy of Sciences
- Journal
- Journal of Applied Physics
- Volume
- 122
- No. of pages
- 6
- ISSN
- 0021-8979
- DOI
- https://doi.org/10.1063/1.4985838
- Publication date
- 09-2017
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103018 Materials physics, 103009 Solid state physics, 103020 Surface physics
- Keywords
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/microscale-magnetic-compasses(4f755d18-da02-411d-81d5-918c8b12ce9c).html