Title :
Structural Characterization and Temperature Dependence of Tunnel Magnetoresistance in Epitaxial Fe/MgO/Fe Junctions
Author :
Wang, S.G. ; Ward, R.C.C. ; Du, G.X. ; Han, X.F. ; Wang, C. ; Kohn, A.
Author_Institution :
Dept. of Phys., Univ. of Oxford, Oxford
Abstract :
Epitaxial Fe/MgO/Fe magnetic tunnel junctions (MTJs) were grown on MgO(001) substrates by molecular beam epitaxy. The epitaxial structure has been characterized using in-situ reflection high energy diffraction, ex-situ X-ray diffraction, and high-resolution transmission electron microscopy. The magnetic and transport properties have been investigated using vibrating sample magnetometry and physical properties measurement system. The temperature dependence of the TMR ratio, whose value rises from 170% at room temperature to 318% at 10 K, is found to be nonlinear and is fitted using a model based on the effect of magnetic disorder of the electrodes on the spin polarized tunneling.
Keywords :
X-ray diffraction; iron; magnesium compounds; magnetic epitaxial layers; magnetic multilayers; magnetic tunnelling; molecular beam epitaxial growth; reflection high energy electron diffraction; spin polarised transport; transmission electron microscopy; tunnelling magnetoresistance; Fe-MgO-Fe; MgO; MgO(001) substrates; TMR ratio; X-ray diffraction; electrodes; epitaxial magnetic tunnel junctions; epitaxial structure; high-resolution transmission electron microscopy; magnetic properties; molecular beam epitaxial growth; physical properties; reflection high energy diffraction; spin polarized tunneling; temperature 10 K; temperature 293 K to 298 K; transport properties; tunnel magnetoresistance; vibrating sample magnetometry; Magnetic Tunnel Junctions (MTJs); Magnetic disorder; Molecular Beam Epitaxy (MBE);
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2008.2002402
