Theory of tunneling magnetoresistance in a disordered Fe/MgO/Fe(001) junction
نویسندگان
چکیده
Calculation of the tunneling magnetoresistance TMR of an Fe/MgO/Fe 001 junction with a disordered Fe/MgO interface is reported. It is shown that intermixing of Fe and Mg atoms at the interface decreases the TMR ratio rapidly and when about 16% of interfacial Fe atoms are substituted by Mg the calculated TMR saturates with increasing MgO thickness in good agreement with experiment. It is demonstrated that the saturation of TMR occurs because interfacial scattering leads to a redistribution of conductance channels, which opens up the perpendicular tunneling channel in the antiferromagnetic configuration that is forbidden for a perfect epitaxial junction.
منابع مشابه
Theory of tunneling magnetoresistance of an epitaxial FeÕMgOÕFe„001... junction
Calculation of the tunneling magnetoresistance ~TMR! of an epitaxial Fe/MgO/Fe~001! junction is reported. The conductances of the junction in its ferromagnetic and antiferromagnetic configurations are determined without any approximations from the real-space Kubo formula using tight-binding bands fitted to an ab initio band structure of iron and MgO. The calculated optimistic TMR ratio is in ex...
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