Ferromagnetic domain wall manipulation using optically induced thermal gradients

Magnetic domain walls are building blocks of both contemporary and futuristic computer memories. Manipulation of the domain walls via external stimuli is thus of a particular technological interest. In our recent contribution in the Journal of Magnetism and Magnetic Materials, we study domain wall movement in response to a thermal gradient. We induce localized thermal gradients in [Co/Pt]₃ multilayer, which exhibits all-optical switching, through femtosecond laser beam illumination and investigate the structure of emerging magnetic domains. X-ray magnetic circular dichroism imaging with a resolution of ~30 nm allows us to provide a parameter space for the domain wall formation spanning the laser pulse number, repetition rate, and fluence. Importantly, we show that the resulting magnetic domains can be oriented by breaking the symmetry of the thermal gradient. The findings further the application potential of the toolbox for domain wall manipulation.