Single laser pulse induced magnetization switching in in-plane magnetized GdCo alloys
Jun‐Xiao Lin, M. Hehn, Thomas Hauet, Peng Yi, Junta Igarashi, Yann Le Guen, Quentin Remy, Jon Gorchon, G. Malinowski, S. Mangin, J. Hohlfeld
Abstract
The discovery of all-optical ultrafast deterministic magnetization switching has opened up new possibilities for manipulating magnetization in devices using femtosecond laser pulses. Previous studies on single pulse all-optical helicity-independent switching (AO-HIS) have mainly focused on perpendicularly magnetized thin films. This work presents a comprehensive study on AO-HIS for in-plane magnetized ${\mathrm{Gd}}_{\mathrm{x}}{\mathrm{Co}}_{100\ensuremath{-}\mathrm{x}}$ thin films. Deterministic single femtosecond laser pulse toggle magnetization switching is demonstrated in a wider concentration range $(x=10\ensuremath{-}25%)$ compared to the perpendicularly magnetized counterparts with GdCo thicknesses up to 30 nm. The switching time strongly depends on the ${\mathrm{Gd}}_{\mathrm{x}}{\mathrm{Co}}_{100\ensuremath{-}\mathrm{x}}$ concentration, with lower Gd concentration exhibiting shorter switching times (less than 500 fs). Our findings in this geometry provide insights into the underlying mechanisms governing single pulse AO-HIS, which challenge existing theoretical predictions. Moreover, in-plane magnetized ${\mathrm{Gd}}_{\mathrm{x}}{\mathrm{Co}}_{100\ensuremath{-}\mathrm{x}}$ thin films offer extended potential for optospintronic applications compared to their perpendicular magnetized counterparts.