Study on magnetic instability of GMR heads using quasi-static tester with laser heating function ☆

A Quasi-static tester (QST) with semiconductor laser heating was developed for GMR heads. We studied the magnetic instability of GMR heads by using the QST and micro-magnetic simulation. It was found from the magnetic simulations that the heads with high domain-control-value at room temperature had also good stability at high-temperature environment as well.