Magnetotransport in MgO-based magnetic tunnel junctions grown by molecular beam epitaxy (invited)

Abstract : The strong impact of molecular beam epitaxy growth and Synchrotron Radiation characterization tools in the understanding of fundamental issues in nanomagnetism and spintronics is illustrated through the example of fully epitaxial MgO-based Magnetic Tunnel Junctions (MTJs). If ab initio calculations predict very high tunnel magnetoresistance (TMR) in such devices, some discrepancy between theory and experiments still exists. The influence of imperfections in real systems has thus to be considered like surface contaminations, structural defects, unexpected electronic states, etc. The influence of possible oxygen contamination at the Fe/MgO(001) interface is thus studied, and is shown to be not so detrimental to TMR as predicted by ab initio calculations. On the contrary, the decrease of dislocations density in the MgO barrier of MTJs using Fe1-xVx electrodes is shown to significantly increase TMR. Finally, unexpected transport properties in Fe1-XCox/MgO/Fe1-XCox (001) are presented. With the help of spin and symmetry resolved photoemission and ab initio calculation, the TMR decrease for Co content higher than 25% is shown to come from the existence of an interface state and the shift of the empty Delta 1 minority spin state towards the Fermi level.
Complete list of metadatas

Cited literature [25 references]  Display  Hide  Download

https://hal.archives-ouvertes.fr/hal-01282615
Contributor : Ijl Ul <>
Submitted on : Tuesday, August 16, 2016 - 1:54:46 PM
Last modification on : Monday, January 13, 2020 - 10:46:02 PM
Long-term archiving on: Thursday, November 17, 2016 - 10:55:06 AM

File

papier-FeCo-MMM2013_23oct2013....
Files produced by the author(s)

Identifiers

Citation

Stéphane Andrieu, F. Bonell, Thomas Hauet, François Montaigne, Lionel Calmels, et al.. Magnetotransport in MgO-based magnetic tunnel junctions grown by molecular beam epitaxy (invited). Journal of Applied Physics, American Institute of Physics, 2014, 115 (17), pp.172610. ⟨10.1063/1.4869824⟩. ⟨hal-01282615⟩

Share

Metrics

Record views

393

Files downloads

220