AVS 47th International Symposium
    Magnetic Interfaces and Nanostructures Wednesday Sessions
       Session MI+EL-WeA

Paper MI+EL-WeA5
Ferromagnetic Fe/Ag-GaAs Waveguide Structures for Wideband Microwave Notch Filter Devices

Wednesday, October 4, 2000, 3:20 pm, Room 206

Session: Magnetic Semiconductors and Hybrid Structures II
Presenter: W. Wu, University of California, Irvine
Authors: W. Wu, University of California, Irvine
C.S. Tsai, University of California, Irvine and Academia Sinica, Taiwan
C.C. Lee, University of California, Irvine
H.J. Yoo, University of California, Irvine
J. Su, University of California, Irvine
Correspondent: Click to Email
Ferromagnetic Fe/Ag thin films were epitaxially grown on GaAs substrate by molecule beam epitaxy (MBE) system. Magneto-optic kerr effect (MOKE) experiment was used to measure the magnetization and sample magnetic anisotropy. Ferromagnetic resonance (FMR) peak-to-peak linewidths @delta@H@sub pp@ are identified with the narrowest linewidth of 23 Oe. Wideband electronically tunable microwave band-stop filters were successfully fabricated utilizing both the flip-chip and the integrated configurations, using Fe/Ag-GaAs waveguide structures. The coupling between the microwave signal and the spin excitations happened in ferromagnetic Fe films. Maximum coupling and thus strong attenuation of the microwave power occur at the FMR frequency of Fe, as determined by the applied magnetic fields. A frequency tuning range of 10.6 to 27.0 GHz has been measured with the flip-chip type filter. For the integrated type filter, a tuning range as large as 10.7 to 36 GHz for the peak absorption carrier frequency of a propagating microwave has been accomplished by varying a magnetic field from 0 to 4,600 Oe. Our studies show that Fe/Ag-GaAs waveguide structure is a very promising system for use in future microwave magnetoelectronics as they have well-defined magnetic properties, as well as favorable electrical properties.