Nitrogen-vacancy-center imaging of bubble domains in a 6-Å film of cobalt with perpendicular magnetization

We employ a scanning nitrogen-vacancy-center microscope to perform stray field imaging of bubble magnetic domains in a perpendicularly magnetized Pt/Co/AlOx trilayer with 6 Å of Co. The stray field created by the domain walls is quantitatively mapped with few-nanometer spatial resolution, with a probe-sample distance of about 100 nm. As an example of application, we show that it should be possible to determine the Bloch or Néel nature of the domain walls, which is of crucial importance to the understanding of current-controlled domain wall motion.