Local control of magnetic interface effects in chiral <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi mathvariant="normal">Ir</mml:mi><mml:mo>|</mml:mo><mml:mi mathvariant="normal">Co</mml:mi><mml:mo>|</mml:mo><mml:mi mathvariant="normal">Pt</mml:mi></mml:math> multilayers using <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mi mathvariant="normal">Ga</mml:mi><mml:mo>+</mml:mo></mml:msup></mml:math> ion irradiation
Mark C. H. de Jong, Mariëlle J. Meijer, Juriaan Lucassen, Jos van Liempt, H. J. M. Swagten, B. Koopmans, Reinoud Lavrijsen
Abstract
In this work we investigate local tuning of the iDMI and perpendicular magnetic anisotropy (PMA) using focused ${\mathrm{Ga}}^{+}$ ion beam irradiation, in an $\mathrm{Ir}|\mathrm{Co}|\mathrm{Pt}$ multilayer system. We show that the magnitude of the interface contribution to both effects can be significantly reduced by the irradiation with ${\mathrm{Ga}}^{+}$ ions. This leads to a reduction by a factor of 2 of the domain wall energy density, while still preserving the N\'eel character of the domain walls. Hence, we postulate that ${\mathrm{Ga}}^{+}$ ion irradiation is an effective way to locally reduce the energy barrier for skyrmion nucleation, providing a novel pathway for targeted skyrmion nucleation in racetrack type devices.