Extending the Snoek’s limit of single layer film in (Co96Zr4∕Cu)n multilayers

Abstract

The present work investigates the high frequency characteristics of (Co96Zr4∕Cu)n multilayers. The results reveal that the Snoek’s limit of (Co96Zr4∕Cu)n multilayers (revised Acher’s limit) are much larger (as a fact 1.76 for some samples) than that of single layer {Acher’s limit [O. Acher and A. L. Adenot, Phys. Rev. B 62, 11324 (2000)]} by comparing their static and dynamic magnetism. It is found that the differences of Acher’s limit between multilayers and single layers are caused by magnetic interface anisotropy. This work might facilitate search for new materials with high permeability at high frequency.