Tunable magnet-less non-reciprocal metamaterial (MNM) and its application to an isolator

We recently introduced magnet-less non-reciprocal metamaterials (MNMs), which are metamaterials composed of traveling-wave ring particles loaded by field effect transistors. MNMs exhibit essentially the same properties as magnetically biased ferrites, but they are lightweight and fully compatible with microwave integrated circuits, due to the absence of rare earths and magnets. We add here electric tunability to MNMs, much easier than magnetic tuning in ferrites, and apply this property to an isolator featuring a tuning range of 400 MHz at 7 GHz with 20 dB isolation.