Micromagnetics of the dynamic susceptibility for coupled Permalloy stripes

The dynamic susceptibility of arrays of narrow Permalloy stripes (9 mm x se veral mum x 200 nm) has been investigated using a single-coil broadband sus ceptibility spectrometer. Disagreement is observed between experimental res ults and the macroscopic Landau-Lifshitz model. This model does not take in to account the dipolar interaction between magnetic stripes. We have perfor med micromagnetic calculations that include these dipolar interactions, and have found the resulting frequency dependence of the dynamic susceptibilit y in the linear regime to be in good agreement with our experimental data. (C) 2000 American Institute of Physics. [S0021-8979(00)03723-3].