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arXiv · 2108.00932

Electric-field control of the exchange interactions

S. Mankovsky·E. Simon·S. Polesya·A. Marmodoro·H. Ebert
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Abstract

The impact of an applied electric field on the exchange coupling parameters has been investigated based on first-principles electronic structure calculations by means of the KKR Green function method. The calculations have been performed for a Fe film, free-standing and deposited on two different substrates, having 1 monolayer (ML) thickness to minimize the effect of screening of the electric field typical for metallic systems. By comparing the results for the free-standing Fe ML with those for Fe on the various substrates, we could analyze the origin of the field-induced change of the exchange interactions. Compared to the free-standing Fe ML, in particular rather pronounced changes have been found for the Fe/Pt(111) system due to the localized electronic states at the Fe/Pt interface, which are strongly affected by the electric field and which play an important role for the Fe-Fe exchange interactions.

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S. Mankovsky, E. Simon, S. Polesya, A. Marmodoro, H. Ebert. 2021-08-02. Electric-field control of the exchange interactions. https://doi.org/10.1103/physrevb.104.174443

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