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arXiv · 1608.05568

Progressive magnetic softening of ferromagnetic layers in multilayer ferromagnet-nonmagnet systems and the role of granularity

Siddharth S. Sahu·Vantari Siva·Paresh C. Pradhan·Maheswar Nayak·Kartik Senapati·Pratap K. Sahoo
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Abstract

We report a study of the structural and magnetic behavior of the topmost magnetic layer in a ferromagnet-nonmagnet (Co-Au) multilayer system. Glancing angle X-ray diffraction measurements performed on a series of multilayers showed a gradually increasing degree of amorphization of the topmost magnetic layer with increasing number of bilayers. Concurrently, the magnetic hardness and magneto-crystalline anisotropy of the top Co layer were found to decrease, as observed by magneto-optical Kerr effect measurements. This magnetic softening has been discussed in the light of Herzer's random anisotropy model. Micromagnetic simulations of the multilayer system also corroborated these observations.

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Siddharth S. Sahu, Vantari Siva, Paresh C. Pradhan, Maheswar Nayak, Kartik Senapati, Pratap K. Sahoo. 2016-08-19. Progressive magnetic softening of ferromagnetic layers in multilayer ferromagnet-nonmagnet systems and the role of granularity. https://doi.org/10.1063/1.4985120

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