Influence of the Magnetic State on the Chemical Order-Disorder Transition Temperature in Fe-Ni Permalloy
2010 (English)In: Physical Review Letters, ISSN 0031-9007, Vol. 105, no 16, 167208- p.Article in journal (Refereed) Published
In magnetic alloys, the effect of finite temperature magnetic excitations on phase stability below the Curie temperature is poorly investigated, although many systems undergo phase transitions in this temperature range. We consider random Ni-rich Fe-Ni alloys, which undergo chemical order-disorder transition approximately 100 K below their Curie temperature, to demonstrate from ab initio calculations that deviations of the global magnetic state from ideal ferromagnetic order due to temperature induced magnetization reduction have a crucial effect on the chemical transition temperature. We propose a scheme where the magnetic state is described by partially disordered local magnetic moments, which in combination with Heisenberg Monte Carlo simulations of the magnetization allows us to reproduce the transition temperature in good agreement with experimental data.
Place, publisher, year, edition, pages
2010. Vol. 105, no 16, 167208- p.
IdentifiersURN: urn:nbn:se:kth:diva-26248DOI: 10.1103/PhysRevLett.105.167208ISI: 000283056100008ScopusID: 2-s2.0-77958141910OAI: oai:DiVA.org:kth-26248DiVA: diva2:397275
FunderSwedish Research CouncilSwedish e‐Science Research Center
QC 201102142011-02-142010-11-212012-05-24Bibliographically approved