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arXiv · 1110.6339

Diffusion thermopower of (Ga,Mn)As/GaAs tunnel junctions

Ts. Naydenova·P. Dürrenfeld·K. Tavakoli·N. Pegard·L. Ebel·K. Pappert·K. Brunner·C. Gould·L. W. Molenkamp
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Abstract

We report the observation of tunneling anisotropic magnetothermopower, a voltage response to a temperature difference across an interface between a normal and a magnetic semiconductor. The resulting voltage is related to the energy derivative of the density of states in the magnetic material, and thus has a strongly anisotropic response to the direction of magnetization in the material. The effect will have relevance to the operation of semiconductor spintronic devices, and may indeed already play a role in correctly interpreting the details of some earlier spin injection studies.

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Ts. Naydenova, P. Dürrenfeld, K. Tavakoli, N. Pegard, L. Ebel, K. Pappert, K. Brunner, C. Gould, L. W. Molenkamp. 2011-10-28. Diffusion thermopower of (Ga,Mn)As/GaAs tunnel junctions. https://doi.org/10.1103/physrevlett.107.197201

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