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arXiv · 1208.3525

Biaxial strain effect of spin dependent tunneling in MgO magnetic tunnel junctions

Ajeesh M. Sahadevan·Ravi K. Tiwari·Gopinadhan Kalon·Charanjit S. Bhatia·Mark Saeys·Hyunsoo Yang
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Abstract

We study the effect of strain on magnetic tunnel junctions (MTJ) induced by a diamond like carbon (DLC) film. The junction resistance as well as the tunnel magnetoresistance (TMR) reduces with the DLC film. Non-equilibrium Green's function quantum transport calculations show that the application of biaxial strain increases the conductance for both the parallel and anti-parallel configurations. However, the conductance for the minority channel and for the anti-parallel configuration is significantly more sensitive to strain, which drastically increases transmission through a MgO tunnel barrier, therefore, the TMR ratio decreases with biaxial strain.

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Ajeesh M. Sahadevan, Ravi K. Tiwari, Gopinadhan Kalon, Charanjit S. Bhatia, Mark Saeys, Hyunsoo Yang. 2012-08-17. Biaxial strain effect of spin dependent tunneling in MgO magnetic tunnel junctions. https://doi.org/10.1063/1.4738787

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