Precessional reversal in exchange-coupled composite magnetic elements

Magnetization reversal in composite exchange-coupled dual-layer magnetic elements can occur in the regime of precessional reversal. Compared to the regime of damping reversal in composite elements, the regime of precessional reversal exhibits substantially reduced reversal fields with modified angular dependence. Precessional reversal in the composite elements can occur for write field rise times of more than an order larger than those in homogeneous (single-layer) elements. Such long rise times can be achieved in practical writing systems even for materials with an ultrahigh anisotropy. The identified phenomena have potential applications in high density hard drives and magnetic random access memory systems.

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