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arXiv · 2004.02175

Domain wall diode based on functionally graded Dzyaloshinskii-Moriya interaction

Kostiantyn V. Yershov·Volodymyr P. Kravchuk·Denis D. Sheka·Jeroen van den Brink·Avadh Saxena
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Abstract

We present a general approach for studying the dynamics of domain walls in biaxial ferromagnetic stripes with functionally graded Dzyaloshinskii-Moriya interaction (DMI). By engineering the spatial profile of the DMI parameter we propose the concept of a diode, which implements filtering of domain walls of certain topological charge and helicity. We base our study on phenomenological Landau-Lifshitz-Gilbert equations with additional Zhang-Li spin-transfer terms using a collective variable approach. In the effective equations of motion the gradients of DMI play the role of a driving force which competes with current driving. All analytical predictions are confirmed by numerical simulations.

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BibTeXRIS

Kostiantyn V. Yershov, Volodymyr P. Kravchuk, Denis D. Sheka, Jeroen van den Brink, Avadh Saxena. 2020-04-05. Domain wall diode based on functionally graded Dzyaloshinskii-Moriya interaction. https://doi.org/10.1063/5.0010107

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