An exchange-biased spin valve with Conetic-based free layers of Co 90Fe 10, Co 90Fe 10/Conetic and Conetic was investigated. The spin valve with the Co 90Fe 10 free layer showed the highest giant magnetoresistance (GMR) ratio of 4% but showed the lowest normalized sensitivity of 0.02 Oe -1. The GMR ratio of 3% and the normalized sensitivity of 0.07 Oe -1 were obtained for the spin valve with the Co 90Fe 10/Conetic free layer after annealing. The spin valve having the Conetic free layer showed softer magnetic properties and well-defined smaller anisotropy than the other spin valves. Though the spin valve showed the lowest GMR of 0.4% after annealing, it showed the highest normalized sensitivity of 0.14 Oe -1. Our study shows that further improvement in MR response of spin valves with Conetic-based free layers can make a spin valve sensor promising for detecting extremely low fields.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)