ESDによるスピンバルブヘッドのピン層磁化反転過程  [in Japanese] Local Magnetization Reversal of the Pinned Layer in a Spin-Valve Head by ESD  [in Japanese]

We measured the micro-track profiles of spin-valve heads after damage by ESD. The output was reduced and the profiles showed several peaks depending on the ESD voltage. We proposed two models for the magnetization reversal process of the pinned layer in the spin-valve heads, and calculated the micro-track profiles by using 3D micro-magnetic simulation In the ferst model, the pinned layer magnetization is gradually rotated as the ESD voltage is increased. In the second model, the direction of the pinned layer magnetization is reversed in the center of the spin-valve element and the reversal region width is increased as the ESD voltage is increased. The calculation results for the second model agreed fairly well with the experimental results. We think that at first the pinned layer magnetization is locally reversed in the center of the element after ESD in the spin-valve head.