Direct detection of nonlinear ferromagnetic resonance in thin films by the magneto-optical Kerr effect.
The longitudinal magneto-optical Kerr effect is used to obtain a calibrated measure of the dynamic magnetization response over the ferromagnetic resonance (FMR) profile for in-plane magnetized Permalloy films excited with high power in-plane transverse microwave fields at 1.25 to 3.75 GHz and in-plane precession angles up to about 20 degrees. The data provide a profound demonstration of the Suhl threshold effect for parametric spin wave generation for angles above about 14 degrees, the magnetization precession lock-up just above threshold, and the complicated response over the full FMR profile at very high powers.
Gerrits
Thomas
T
National Institute of Standards and Technology, Boulder, Colorado 80305, USA.
Krivosik
Pavol
P
Schneider
Michael L
ML
Patton
Carl E
CE
Silva
T J
TJ