Abstract
We study ferromagnetic transition in three-dimensional double-exchange model containing impurities. The influence of both spin fluctuations and impurity potential on conduction electrons is described in coherent potential approximation. In the framework of thermodynamic approach we construct Landau functional for the system "electrons (in disordered environment) + core spins". Analyzing the Landau functional we calculate the temperature of ferromagnetic transition TC and paramagnetic susceptibility χ. For TC, we thus extend the result obtained by Furukawa in the framework of the dynamical mean field approximation, with which our result coincides in the limit of zero impurity potential. We find, that the alloy disorder, able to produce a gap in density of electron states, can substantially decrease TC with respect to the case of no impurities. We also study the general relation between the coherent potential approximation and the dynamical mean field approximation.
| Original language | English |
|---|---|
| Pages (from-to) | 345-358 |
| Number of pages | 14 |
| Journal | Physica A: Statistical Mechanics and its Applications |
| Volume | 302 |
| Issue number | 1-4 |
| DOIs | |
| State | Published - 15 Dec 2001 |
| Event | International Workshop on Frontiers in the Physics of Complex Systems - Ramat-Gan, Israel Duration: 25 Mar 2001 → 28 Mar 2001 |
Keywords
- Alloy disorder
- Coherent potential approximation
- Dynamical mean field theory
- Ferromagnetic transition
- Manganites
- Strongly correlated system
ASJC Scopus subject areas
- Statistics and Probability
- Condensed Matter Physics