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arXiv · 1812.06096

Current Control of Magnetism in Two-Dimensional Fe3GeTe2

Øyvind Johansen·Vetle Risinggård·Asle Sudbø·Jacob Linder·Arne Brataas
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Abstract

The recent discovery of magnetism in two-dimensional van der Waals systems opens the door to discovering exciting physics. We investigate how a current can control the ferromagnetic properties of such materials. Using symmetry arguments, we identify a recently realized system in which the current-induced spin torque is particularly simple and powerful. In Fe3GeTe2, a single parameter determines the strength of the spin-orbit torque for a uniform magnetization. The spin-orbit torque acts as an effective out-of-equilibrium free energy. The contribution of the spin-orbit torque to the effective free energy introduces new in-plane magnetic anisotropies to the system. Therefore, we can tune the system from an easy-axis ferromagnet via an easy-plane ferromagnet to another easy-axis ferromagnet with increasing current density. This finding enables unprecedented control and provides the possibility to study the Berezinskii-Kosterlitz-Thouless phase transition in the 2D XY model and its associated critical exponents.

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Øyvind Johansen, Vetle Risinggård, Asle Sudbø, Jacob Linder, Arne Brataas. 2019-01-03. Current Control of Magnetism in Two-Dimensional Fe3GeTe2. https://doi.org/10.1103/physrevlett.122.217203

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