Nonreciprocal millimeter-wave devices using a solid-state plasma at room temperature

We have demonstrated nonreciprocal millimeter-wave properties, first observed by us, in a waveguide loaded with a thin slab of n-InSb at room temperature by the construction of three kinds of nonreciprocal devices, all operating at W-band frequencies. Measurements have shown that the nonreciprocal properties previously observed at K-band are indeed maintained from the microwave to the millimeter-wave region and the characteristics of our devices are comparable with those we developed at K-band frequencies. These results show that the development of practical solid-state wide-band nonreciprocal millimeter-wave devices should be possible.