Skip to content

Single-spin sensing of domain-wall structure and dynamics in a thin-film skyrmion host

MetadataDetails
Publication Date2019-08-01
JournalPhysical Review Materials
AuthorsAlec Jenkins, Matthew Pelliccione, Guoqiang Yu, Xin Ma, Xiaoqin Li
InstitutionsUniversity of California, Los Angeles, The University of Texas at Austin
Citations38

Skyrmions are nanoscale magnetic structures with features promising for future low-power memory or logic devices. In this work, we demonstrate scanning techniques based on nitrogen vacancy center magnetometry that simultaneously probe both the magnetic dynamics and structure of room temperature skyrmion bubbles in a thin-film system Ta/CoFeB/MgO. We confirm the handedness of the Dzyaloshinskii-Moriya interaction in this material and extract the magnitude of the helicity angle of the skyrmion bubbles. Our measurements also show that the skyrmion bubbles in this material change size in discrete steps, dependent on the local pinning environment, with their average size determined dynamically as their domain walls hop between pinning sites. In addition, an increase in magnetic field noise is observed near skyrmion bubble domain walls. These measurements highlight the importance of interactions between internal degrees of freedom of skyrmion bubble domain walls and pinning sites in thin-film systems. Furthermore, our observations have relevance for future devices based on skyrmion bubbles where pinning interactions will determine important aspects of current-driven motion.