Giant magneto-impedance effect in diamagnetic organic thin film coated amorphous ribbons

We grew a diamagnetic thin film on the surface of Co-based amorphous ribbon (Fe5.85Co70.15Mo4B15Si5) to investigate the effect of this coating on giant magneto-impedance (GMI). We investigated GMI over a frequency range of 0.1–3.0 MHz and under a static magnetic field. The results show that GMI for amorphous ribbons can be enhanced by this coating process. A changing in GMI as high as 90% was observed in diamagnetic organic thin film coated Co-based amorphous ribbons at 2 MHz. The very large enhancement of the GMI value is a consequence of the closed magnetic flux path under the organic film layer. In this work, we concentrated on enhancing the GMI effect. First, we show that sensitivities of the ribbons can be improved by using the coating technique. In addition, the surfaces of these samples were imaged and analyzed by an atomic force microscopy.