Data-Perpendicular Reading Of Single Confined Magnetic Skyrmions

Thin-film sub-5 nm magnetic skyrmions constitute an ultimate scaling alternative for future<br> digital data storage. Skyrmions are robust noncollinear spin textures that can be moved and<br> manipulated by small electrical currents. Here we show here a technique to detect isolated<br> nanoskyrmions with a current perpendicular-to-plane geometry, which has immediate<br> implications for device concepts. We explore the physics behind such a mechanism by<br> studying the atomistic electronic structure of the magnetic quasiparticles. We investigate<br> from first principles how the isolated skyrmion local-density-of-states which tunnels into<br> the vacuum, when compared with the ferromagnetic background, is modified by the site<br> dependent spin mixing of electronic states with different relative canting angles. Local<br> transport properties are sensitive to this effect, as we report an atomistic conductance<br> anisotropy of up toB20% for magnetic skyrmions in Pd/Fe/Ir(111) thin films. In single<br> skyrmions, engineering this spin-mixing magnetoresistance could possibly be incorporated in<br> future magnetic storage technologies.