Scanning Nitrogen-Vacancy Center Magnetic Imaging of Skyrmions*

Topological excitations in thin-film magnetic systems, known as skyrmions, have been proposed as the basis of near-future, high density and low power memory devices. Before practical devices based on these excitations can be realized, new materials must be designed that maximize skyrmion current-driven velocities, minimize the depinning current densities, and host nanoscale skyrmions at length scales competitive with existing technologies (<100 nm). In this work, we utilize a scanning probe based on the nitrogen-vacancy center in diamond to magnetically image skyrmions with high spatial resolution, revealing variation and fluctuation of their shape. We observe hints of the interplay between skyrmion domain wall dynamics and pinning sites, an understanding of which will be important for future device applications.