Domain wall pinning in narrow ferromagnetic ring structures probed by magnetoresistance measurements.
We present a magnetoresistance study of magnetization reversal and domain wall pinning effects in a mesoscopic narrow ferromagnetic Permalloy ring structure containing notches. The size and strength of the attractive pinning potential created by a notch is measured and the resistance minimum at remanence is found to occur when a single transverse domain wall is pinned at the notch, in agreement with the results of numerical simulations of the anisotropic magnetoresistance. When a field is applied in the direction corresponding to a potential well edge, a novel magnetic state with a very wide domain wall is stabilized, giving rise to a characteristic signature in the magnetoresistance at such angles.
Kläui
M
M
Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 OHE, United Kingdom.
Vaz
C A F
CA
Rothman
J
J
Bland
J A C
JA
Wernsdorfer
W
W
Faini
G
G
Cambril
E
E