Dependence of the giant magnetoimpedance on electron irradiation for bio-sensor design

The effects of electron irradiation on the giant magnetoimpedance (GMI) have been investigated for a Co-based amorphous ribbon. The GMI ratio was used to characterize the samples before and after the electron irradiation. The GMI ratio was increased considerably in the electron-irradiated samples, and the GMI response showed a strong dependence on the electron irradiation time and driving frequencies. The electron irradiation was shown to lead to a substantial modification of the magnetic properties. Our studies indicate that low-energy election irradiation is useful for improving the magnetic GMI, which is of practical importance for the development of high-performance bio-magnetic sensors.