Abstract
Zero- and finite-temperature coercivity mechanisms in disordered nanostructures are investigated by model calculations. Three different aspects are considered. First, it is shown that strongly reduced exchange in grain-boundary regions changes the power-law scaling exponent for the coercivity of random-anisotropy magnets. Second, it is analyzed how random interatomic exchange affects the thermal blocking and therefore the coercivity of spin glasses. Third, a master-equation approach is used to quantitatively elucidate the relation between the magnetic-viscosity regime and the sweep-rate dependence of the coercivity. A common feature of the considered mechanisms is that interatomic exchange creates nanoscale cooperative units which realize the coercivity in real space.
Original language | English (US) |
---|---|
Pages (from-to) | 857-862 |
Number of pages | 6 |
Journal | Scripta Materialia |
Volume | 48 |
Issue number | 7 |
DOIs | |
State | Published - Apr 1 2003 |
Keywords
- Coercivity
- Free energy
- Magnetic viscosity
- Magnetization dynamics
- Random anisotropy
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys