Chiral spin textures such as magnetic skyrmions represent the smallest realizable emergent magnetic entities in functional materials. Their topological stability and ease of tunability in ultrathin magnetic films has generated considerable promise as robust, mobile bits for sustainable computing [1]. While spin textures are readily visualized using several magnetic imaging techniques, their electrical detection has been a topic of intense research and debate [2].
Here, we establish robust electrical signatures of individual and ensemble spin textures stabilized across a tunable material platform [3-5]. First, we examine Hall transport across spin texture ensembles. In contrast to the claimed presence of a topological Hall effect, our systematic study unveils an unconventional anomalous Hall effect, which derives from the geometric morphology of spin textures [6]. Next, we show that the microwave spectrum of spin textures universally hosts a trifecta of resonance modes arising from irreversible transitions. In multilayers, their high-frequency spectrum can be deterministically and widely modulated via in situ analogue knobs [7]. Finally, we present a nanoscale magnetic tunnel junction (MTJ) hosting a single, ambient skyrmion [8]. The MTJ nucleates skyrmions of fixed polarity, albeit via two distinct mechanisms, with readout signal quantifying skyrmion size. Crucially, it can electrically write and delete skyrmions to both uniform states with energies 1,000 times lower than state-of-the-art MTJs. Here, the applied voltage emulates a magnetic field, and reshapes both the transition energetics and kinetics. Demonstrations of skyrmion readout, switching, and motion establish a much-anticipated backbone for all-electrical skyrmionics.

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More information :https://www.spintec.fr/seminar-decoding-electrical-signatures-of-chiral-spin-textures/​

Videoconference ​: https://webconf.cea.fr/olivier.boulle/5GFYNR49​​​