Wideband tunable microwave devices using ferromagnetic film-gallium arsenide material structures

Yittrium iron garnet (YIG)-gadolinium gallium garnet (GGG) and iron (Fe)-gallium arsenide (GaAs) layer structures have been used, respectively, to construct wideband tunable microwave bandstop filters of the flip-chip type and the integrated type. For the former, a frequency tuning range of 2.5-23.0 GHz was accomplished at a magnetic field tuning range of 290-7300 Oe. For the latter, a comparable tuning bandwidth but of significantly higher carrier frequencies of 10.7-32.5 GHz has been achieved at a much lower magnetic field tuning range, namely, 0-4500 Oe. The advantages associated with the Fe-film-based bandstop filters should also accompany other analog microwave devices