Elaboration et caractérisation de nanostructures de FeRh structure, ordre chimique et transition magnétique

Marion Castiella 1
1 CEMES-SINanO - Surfaces, Interfaces et Nano-Objets
CEMES - Centre d'élaboration de matériaux et d'études structurales
Abstract : With the increasing demand for ultra-high density magnetic recording, an important effort was put on fabrication and control of magnetic nanoalloys. Indeed, magnetic alloys possess much more interesting properties than magnetic pure metals in particular chemically ordered alloys (higher magnetic anisotropy). When these alloys have a nanometer size, their properties may change significantly. In the last decade, much attention has been paid to the remarkable magnetic properties of the FeRh ordered alloy, for both fundamental and technological issues. Indeed, the FeRh alloy presents, in a very narrow range of composition close to the equiatomic one, a magnetic transition from antiferromagnetic (AFM) to ferromagnetic (FM) state. This transition takes place at a temperature close to 370K in the bulk, i.e. slightly higher than room temperature, which make with alloy particularly attractive for applications as heat-assisted magnetic recording or for microelectronics. The present work focuses on the fabrication and study of FeRh nanostructures with different morphologies. All the nanostructures were grown by dc magnetron sputtering in an ultra-high vacuum chamber. Particular attention was paid to the evolution of the structural, and eventually magnetic, characteristics of the nanostructures as the function of their size and the growth conditions. Two types of nanostructures were studied: thin films epitaxially grown on MgO (001) and nanoparticles embedded in an amorphous alumina matrix. The evolution of the morphological chemical and structural characteristics was analyzed by high-angle X-ray diffraction (XRD) and by transmission electron microscopy (TEM) and associated spectroscopies. Magnetic properties were studied by vibrating sample magnetometer and in-situ in a microscope by electronic holography.
Complete list of metadatas

Cited literature [100 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01341603
Contributor : Abes Star <>
Submitted on : Monday, July 4, 2016 - 2:49:08 PM
Last modification on : Monday, April 29, 2019 - 4:05:17 PM
Long-term archiving on : Wednesday, October 5, 2016 - 2:57:21 PM

File

2015TOU30293.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01341603, version 1

Citation

Marion Castiella. Elaboration et caractérisation de nanostructures de FeRh structure, ordre chimique et transition magnétique. Mécanique des matériaux [physics.class-ph]. Université Paul Sabatier - Toulouse III, 2015. Français. ⟨NNT : 2015TOU30293⟩. ⟨tel-01341603⟩

Share

Metrics

Record views

265

Files downloads

321