Temperature dependence of the resistance of magnetic tunnel junctions with MgO barrier

The temperature dependent tunneling resistance of magnetic tunnel junctions with MgO barriers was characterized. In the junctions prepared by magnetron sputtering, the tunnel magnetoresistance decreases with increasing temperature. Various contributions to the tunnel conductance are discussed using different models. Not only the direct elastic tunneling contributes to the temperature dependence of tunnel magnetoresistance, but also the assisted, spin-independent tunneling plays an important role in determining the temperature dependent behavior in our magnetic tunneling junctions. The process is further investigated assuming magnon and phonon assisted tunneling and compared to junctions with alumina tunnel barrier.

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