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arXiv · 1303.6330

Ab initio studies of the tunneling magneto-Seebeck effect: influence of magnetic material

Christian Heiliger·Christian Franz·Michael Czerner
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Abstract

We found a strong influence of the composition of the magnetic material on the temperature dependence of the tunneling magneto-Seebeck effect in $MgO$ based tunnel junctions. We use \textit{ab initio} alloy theory to consider different $Fe_xCo_{1-x}$ alloys for the ferromagnetic layer. Even a small change of the composition leads to strong changes in the magnitude or even in the sign of the tunneling magneto-Seebeck effect. This can explain differences between recent experimental results. In addition, changing the barrier thickness from six to ten monolayers of $MgO$ leads also to a non-trivial change of the temperature dependence. Our results emphasize that the tunneling magneto-Seebeck effect depends very crucially and is very sensitive to material parameters and show that further experimental and theoretical investigations are necessary.

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Christian Heiliger, Christian Franz, Michael Czerner. 2013-03-25. Ab initio studies of the tunneling magneto-Seebeck effect: influence of magnetic material. https://doi.org/10.1103/physrevb.87.224412

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