TY - JOUR
T1 - Barkhausen Imaging
T2 - A magneto-optical approach to mapping the pinning landscape in soft ferromagnetic films
AU - Trimble, J.
AU - Berezovsky, J.
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/4/1
Y1 - 2021/4/1
N2 - We demonstrate a magneto-optical microscopy technique to create two-dimensional images of the pinning behavior of a vortex state as it is translated through a soft ferromagnetic film. The resulting information yields a map of how defects and inhomogeneities in the material serve to trap high-energy-density magnetization configurations such as vortex cores or domain walls. We raster scan a vortex core within a thin permalloy disk using in-plane magnetic fields, and monitor the vortex displacement using the magneto-optical Kerr effect. The differential nature of the measurement yields spatial resolution ≈5 nm, much less than the diffraction limit, and minimum resolvable pinning energy ≈0.4 eV. The technique produces two images, one displaying the pinning-induced vortex displacement relative to the expected free motion, and the other displaying hysteretic vortex displacement between the trace and re-trace. We demonstrate the technique on two samples, extract quantitative statistics about the pinning landscape, and compare to simulated results with a pinning landscape derived from the measured surface topography of the samples.
AB - We demonstrate a magneto-optical microscopy technique to create two-dimensional images of the pinning behavior of a vortex state as it is translated through a soft ferromagnetic film. The resulting information yields a map of how defects and inhomogeneities in the material serve to trap high-energy-density magnetization configurations such as vortex cores or domain walls. We raster scan a vortex core within a thin permalloy disk using in-plane magnetic fields, and monitor the vortex displacement using the magneto-optical Kerr effect. The differential nature of the measurement yields spatial resolution ≈5 nm, much less than the diffraction limit, and minimum resolvable pinning energy ≈0.4 eV. The technique produces two images, one displaying the pinning-induced vortex displacement relative to the expected free motion, and the other displaying hysteretic vortex displacement between the trace and re-trace. We demonstrate the technique on two samples, extract quantitative statistics about the pinning landscape, and compare to simulated results with a pinning landscape derived from the measured surface topography of the samples.
KW - Magneto-optical Kerr effect
KW - Pinning
KW - Vortices
UR - http://www.scopus.com/inward/record.url?scp=85097766816&partnerID=8YFLogxK
U2 - 10.1016/j.jmmm.2020.167585
DO - 10.1016/j.jmmm.2020.167585
M3 - Article
AN - SCOPUS:85097766816
SN - 0304-8853
VL - 523
JO - Journal of Magnetism and Magnetic Materials
JF - Journal of Magnetism and Magnetic Materials
M1 - 167585
ER -