Nonreciprocal microwave devices based on magnetic nanowires

We use magnetic nanowires in an alumina matrix as the active element in microwave nonreciprocal resonance isolators. The design is related to waveguide E-plane isolators but is planar and much smaller than typical waveguide isolators. There is a nonreciprocal attenuation of the wave in forward and reverse directions. The isolation is about 6 dB/cm at 23 GHz. The bandwidth of the device is relatively large (5-7 GHz) in comparison to ferrite-based devices. The central frequency of the device can be tuned with the application of magnetic field.