We study numericaly and analytically a simple model for the magnetic properties of moderately impure (formula presented) (formula presented) compounds. The model largely relies on available experimental results and it is investigated by complementary methods: percolation and Monte Carlo simulations, together with random-field analytical theory. Our results conclusively show a critical change of the magnetic response above a given concentration (formula presented) We find that, beyond this concentration, the unusual features of the spontaneous magnetization observed experimentally result from the coexistence of ferrimagnetic long-range order with cluster superparamagnetism.
|Original language||English (US)|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Jan 1 2001|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics