science24.com - Magnetoresistance effects in phthalocyanine based magnetic tunnel junctions

Search for content and authors

Magnetoresistance effects in phthalocyanine based magnetic tunnel junctions

Clement Barraud ¹, Richard Mattana ¹, Pierre Seneor ¹, Raphael Guillemet ¹, Stephane Fusil ¹, Karim Bouzehouane ¹, Cyrile Deranlot ¹, Frédéric Petroff ¹, Albert Fert ¹, Jean Batiste Beaufrand ², Dong Jik Kim ², Jacek Arabski ², Samy Boukari ², Martin Bowen ², Eric Beaurepaire ²

1. Unité Mixte de Physique CNRS-Thales, Route départementale 128, Palaiseau 91767, France
2. Institut de Physique et Chimie des Materiaux de Strasbourg, UMR7504, CNRS - ULP, 23, rue du Loess, BP 43, Strasbourg CEDEX 2 67034, France

Abstract

Organic spintronics has been the focus of a growing interest since 2002 and the first
observation of magnetoresistance effects through sexithiophene (T₆) films [1]. Since then, most of the successful studies have dealt with aluminium tris(8-hydroxyquinoline) (Alq₃) [2]. Here we report on the fabrication and magneto-transport properties of nanometer size organic magnetic tunnel junctions based on the cobalt-phthalocyanine organic semiconductor.
In order to elaborate these nanometer size tunnel junctions, the fabrication is carried out using a combination of UV lithography and conductive tip AFM nanoindentation process where the tip-sample resistance is monitored in real time [3]. With this technique, we are able to control the section (about few tenth nm²) of the nanocontact. Moreover, by indenting further, we can also vary the organic tunnel barrier thickness. As a final step, cobalt is deposited into the nanocontact forming a magnetic tunnel junction enabling the study spin dependent tunnelling through the CoPc layer.
We have performed spin dependent transport measurements in Co/CoPc/Co magnetic tunnel
junctions where the thickness of the organic semiconductor is only few nm. We have observed a significant magnetoresistance effect (>30 %) at low temperature. Two contributions to the magnetoresistance are isolated: a tunnel anisotropic magnetoresistance (TAMR) and a spin valve effect associated to the magnetic configuration of Co electrodes (parallel and antiparallel magnetic configurations).

[1] V. Dediu et al., Solid State Communication, 122, 181 (2002)
[2] Z.H. Xiong et al., Nature, 427, 821 (2004); L.E. Hueso et al., Adv. Mater. 19, 2639 (2007); T.S Santos et al., Phys. Rev. Lett. 98, 016601 (2007); H. Vinzelberg et al., J.Appl. Phys. 103, 093720 (2008)
[3] K. Bouzehouane et al. Nanolett. 3 1599 (2003)

Legal notice

Legal notice:

Copyright (c) Pielaszek Research, all rights reserved.
The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/19250 must be provided.

Magnetoresistance effects in phthalocyanine based magnetic tunnel junctions

Presentation: Poster at E-MRS Fall Meeting 2009, Symposium E, by Clement Barraud See On-line Journal of E-MRS Fall Meeting 2009 Submitted: 2009-05-25 17:27 Revised: 2009-06-07 00:48

Presentation: Poster at E-MRS Fall Meeting 2009, Symposium E, by Clement Barraud
See On-line Journal of E-MRS Fall Meeting 2009

Submitted: 2009-05-25 17:27 Revised: 2009-06-07 00:48