Angular-momentum-biasing for non-reciprocal electromagnetic devices

A novel method for generating non-reciprocity based on angular-momentum biasing is presented. The new approach does not require ferromagnetic materials or external magnetic fields, eliminating the need for rare-earth materials while at the same time simplifying circuit integration schemes. Waveguide and lumped element resonators are simulated and fabricated to validate the proposed phenomenon. A circulator based on the angular momentum biasing technique is shown to provide over 38 dB of isolation in both microstrip ring and lumped element resonator designs.