Individual skyrmion manipulation by local magnetic field gradients

Arianna Casiraghi, Héctor Corte-León, Mehran Vafaee, Felipe Garcia-Sanchez, Gianfranco Durin, Massimo Pasquale, Gerhard Jakob, Mathias Kläui, Olga Kazakova
2019 Communications Physics  
Magnetic skyrmions are topologically protected spin textures, stabilised in systems with strong Dzyaloshinskii-Moriya interaction (DMI). Several studies have shown that electrical currents can move skyrmions efficiently through spin-orbit torques. While promising for technological applications, current-driven skyrmion motion is intrinsically collective and accompanied by undesired heating effects. Here we demonstrate a new approach to control individual skyrmion positions precisely, which
more » ... cisely, which relies on the magnetic interaction between sample and a magnetic force microscopy (MFM) probe. We investigate perpendicularly magnetised X/CoFeB/MgO multilayers, where for X = W or Pt the DMI is sufficiently strong to allow for skyrmion nucleation in an applied field. We show that these skyrmions can be manipulated individually through the local field gradient generated by the scanning MFM probe with an unprecedented level of accuracy. Furthermore, we show that the probe stray field can assist skyrmion nucleation. Our proof-of-concepts results pave the way towards achieving current-free skyrmion control.
doi:10.1038/s42005-019-0242-5 fatcat:wfpa4555yraydkvp65pazysewy