Slow magnetization dynamics of small permalloy islands
Slow magnetization dynamics of small permalloy islands
Files
Publication or External Link
Date
2000-05-01
Authors
Koo, H.
Luu, T. V.
Gomez, R. D.
Metlushko, V. V.
Advisor
Citation
H.C. Koo, T.V. Luu, V. Metlushko and R.D. Gomez, “Slow magnetization dynamics of small Permalloy islands” Journal of Applied Physics 87 (8), 5114-5116 (2000).
DRUM DOI
Abstract
The conditions that lead to specific domain configurations and the associated switching
characteristics of small permalloy islands were studied by using magnetic force microscopy. By
measuring a large number of particles, it was established that islands that have nonzero remanent
moments ~nonsolenoidal! exist in one of three distinct configurations, namely: ~a! true single
domain, ~b! quasisingle domain with edge closure patterns, and ~c! multidomain with nonuniform
internal magnetization. The configuration depended upon the island width as well as the aspect ratio.
Islands that are 310 nm wide or less are true single domain particles at low aspect ratios
(;1.87) and higher, while islands wider than 500 nm always exhibited edge closure domains even
for very large aspect ratios. In the range between 310 and 500 nm, the onset of single domain
behavior was a function of the aspect ratio and thickness. Our studies involving in situ applied field
similarly revealed the mechanisms of the reversal processes for each of the configurations, which
correlated quite well with the values of the switching fields.