Fabrication of ferromagnetic/semiconductor waveguide structures and application to microwave bandstop filter

We studied the propagation of a microwave signal in Fe/Ag-GaAs waveguide st ructures. In an ultrahigh frequency ferromagnetic resonance measurement, ma ximum coupling and thus strong attenuation of the microwave power occur nea r the ferromagnetic resonance frequency f(res) of Fe film. Magnetostatic wa ve (MSW)-based microwave devices have been achieved in the form of a bandst op filter utilizing single crystal Fe/Ag structures grown on GaAs (100) sub strate. MSW-based microwave devices possess the unique capability of electr onically tunable operating carrier frequency via a magnetic field. The peak absorption frequency for an Fe easy axis case has been tuned in a range fr om 10.6 to 36 GHz. For a hard axis case, the tuning frequency ranges from 8 to 22 GHz. The experimental results show that Fe/Ag-GaAs waveguide structu res are very promising systems for use in future microwave magnetoelectroni cs as they have well-defined magnetic properties, as well as favorable elec trical properties. (C) 2001 American Vacuum Society.