Atomic ordering in nano-layered FePt

Autor(en)

Miroslaw Kozlowski, Rafal Kozubski, Christine Goyhenex, Veronique Pierron-Bohnes, Marcus Rennhofer, S. Malinov

Abstrakt

Monte Carlo simulation of chemical ordering kinetics in nano-layered L1(0) AB binary intermetallics was performed. The study addressed FePt thin layers considered as a material for ultra-high-density magnetic storage media and revealed metastability of the L1(0) c-variant superstructure with monoatomic planes parallel to the surface and off-plane easy magnetization. The layers, originally perfectly ordered in a c-variant of the L1(0) superstructure, showed homogeneous disordering running in parallel with a spontaneous re-orientation of the monoatomic planes leading to a mosaic microstructure composed of a- and b-L1(0)-variant domains. The domains nucleated heterogeneously on the surface of the layer and grew discontinuously inwards its volume. Finally, the domains relaxed towards an equilibrium microstructure of the system. Two "atomistic-scale" processes: (i) homogeneous disordering and (ii) nucleation of the a- and b-L1(0)-variant domains showed characteristic time scales. The same was observed for the domain microstructure relaxation. The discontinuous domain growth showed no definite driving force and proceeded due to thermal fluctuations. The above complex structural evolution has recently been observed experimentally in epitaxially deposited thin films of FePt. (C) 2009 Elsevier Ltd. All rights reserved.

Organisation(en)

Dynamik Kondensierter Systeme

Externe Organisation(en)

Jagiellonian University in Krakow, Université de Strasbourg, University College Dublin

Journal

Intermetallics

Band

17

Seiten

907-913

Anzahl der Seiten

7

ISSN

0966-9795

DOI

https://doi.org/10.1016/j.intermet.2009.03.019

Publikationsdatum

2009

Peer-reviewed

Ja

ÖFOS 2012

1030 Physik, Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/atomic-ordering-in-nanolayered-fept(3d36a30d-f1ba-429f-8a69-f88de8592e8b).html