In the present study, high sensitive detection of the reversible susceptibility modulation in the magnetic thin film was performed by an LC circuit resonant technique. A flat pick-up coil with the inductance of 0.80 μH and a capacitance of 100 pF construct the LC resonant circuit. The reversible susceptibility χ of the magnetic thin film, embedded in the pick-up coil, was measured with a sinusoidal exciting field (H). The out put signal was modulated by applying an orthogonal bias field (Hb). A multilayer sample of [NiFe(100 nm)/Cu(10 nm)20 exhibits the most sensitive modulation effect among the fabricated samples. That is, the resonant frequency fr was decreased from 11.58 MHz (Hb = 0 Oe) to 8.22 MHz (Hb = 7 Oe) at Hex = 2.5 mOe, suggesting the marked increase of χ. The value of Hb, which minimizes f r, is comparable to the anisotropy field. Thus, the observed drastic increase of χ can be associated with the compensation of the anisotropy with Hb, as confirmed from the theoretical prediction. The practical out put voltage change of 55%/Oe was realized for the fabricated resonator.
|Number of pages||5|
|Journal||Research Reports on Information Science and Electrical Engineering of Kyushu University|
|Publication status||Published - Sept 2008|
All Science Journal Classification (ASJC) codes
- Computer Science(all)
- Electrical and Electronic Engineering