Soft x-ray ptychography studies of nanoscale magnetic and structural correlations in thin SmCo5 films*

Soft x-ray ptychographic imaging was applied to probe an amorphous 50 nm thin SmCo5 film prepared by off-axis pulsed laser deposition and exhibiting a strong perpendicular magnetic anisotropy. Amplitude and phase contrast images, retrieved at photon energies near the cobalt L3 resonance, were used to identify and characterize magnetic and structural features with a spatial resolution of about10 nm. Aside from the common magnetic labyrinth domain pattern, nanoscale structural inclusions were identified that are primarily located in close proximity to the magnetic domain walls. X-ray absorption spectroscopy suggests that these inclusions are nanocrystalline Sm2Co17 phases with nominally in-plane magnetic anisotropy. Our results indicate that x-ray ptychographic imaging enables fruitful studies of magnetic and structural correlations at length scales relevant to emerging magnetic and spintronic devices.