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arXiv · 2206.10264

Extrinsic tunnel Hall effect in CoFeB/MgO/Pt junctions

Abstract

The Hall effect that occurs when current flows through a CoFeB/MgO/Pt tunnel junction is investigated. It is shown that the transverse voltage in Pt electrode is nonlinear on a DC voltage applied to the tunnel junction. It has both linear (odd) and quadratic (even) parts. The linear part contains well-known contributions of the anomalous Hall effect in the ferromagnetic electrode, inverse spin-hall effect in platinum and others. The quadratic part is a phenomenon caused by the spin-orbit scattering of electrons in an external electric field induced by a voltage applied to the barrier. This field reaches values of $10^9$ V/m which is close to internal atomic fields. The magnitude of both effects decreases as thickness of Pt electrode is increased due to shunting effects.

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I. Yu. Pashenkin, M. V. Sapozhnikov, N. S. Gusev, E. A. Karashtin, A. A. Fraerman. 2022-06-21. Extrinsic tunnel Hall effect in CoFeB/MgO/Pt junctions. https://doi.org/10.1103/physrevb.106.l220408

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