https://doi.org/10.1140/epjb/e2004-00234-6
Low-height sputter-deposited magnesium oxide tunnel barriers: experimental report and free electron modeling
1
Laboratoire de Physique des Matériaux, UMR CNRS 7556,
B.P. 239, 54506 Vandœuvre-les-Nancy Cedex, France
2
CEMES-CNRS-Groupe NanoMatériaux, 29 rue Jeanne Marvig, B.P. 94347, 31055 Toulouse Cedex,
France
Corresponding author: a hehn@lpm.u-nancy.fr
Received:
16
February
2004
Revised:
23
April
2004
Published online:
3
August
2004
Magnetic tunnel junctions with a barrier of magnesium oxide were prepared by plasma oxidation of sputter-deposited magnesium. They show magnetoresistance ratios up to 4.5% at room temperature and 5.5% at low temperatures for barrier thickness of 1.6 nm. The material exhibits low barrier heights of around 0.7 eV. These junctions follows the predictions of the free electron model which contrast with the predictions of band structure calculations and experimental results on epitaxial MgO based tunnel junctions.
PACS: 73.40.Rw – Metal-insulator-metal structures / 75.70.Pa – Giant magnetoresistance / 73.40.Gk – Tunneling / 73.61.Ng – Insulators
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2004
