Frequency dependence of magneto-impedance in spin tunneling junction

Summary form only given. Spin tunneling junctions (STJ) have potential applications in the next generation of magnetic recording read heads due to the large magnetoresistance ratio. The frequency dependence of the impedance of the tunneling junction is studied and the feasibility of this application is discussed. The tunneling junction, Al/Al/sub 2/O/sub 3//Al, and coercive differential STJ, Co/Al/sub 2/O/sub 3//Co, were fabricated onto glass substrates by ion-beam mask sputtering. The impedance was measured using a vector impedance meter in the frequency range 0.1 to 100 MHz. The results indicate that the change in the imaginary part of the magnetoimpedance must be detected in order to utilize the STJ, particularly in the high-frequency region.