Size effect on single pulse all-optical helicity-independent switching in GdFeCo disk arrays

We experimentally demonstrate single pulse toggle switching of the magnetization of GdFeCo disks with perpendicular to film plane anisotropy, which diameter ranges from 3 mu m to 400 nm using 35 fs linearly polarized laser pulses. Two different magnetic states can be observed depending on the laser fluence: either a deterministic switching of the disk magnetization or a randomly oriented disk. We report that the fluence required to observe both magnetic states show a non-monotonic behavior with disk diameter and that the smallest disks require the lowest minimum fluence for achieving single pulse all-optical helicity-independent switching. Different evolution of the fluence thresholds for both phenomenon as a function of the disk size is observed and discussed.

Automated summary

We demonstrate the single pulse toggle switching of magnetization in GdFeCo disks with perpendicular to film plane anisotropy using 35 fs linearly polarized laser pulses. Two different magnetic states can be observed depending on the laser fluence: deterministic switching or randomly oriented disks. We observe a non-monotonic behavior of fluence thresholds with disk diameter and discuss the different evolution of the thresholds for both phenomenon.