Predicted performance of semiconductor junction circulators with losses

A study of the circulation properties of a gyroelectric medium consisting of a high-quality n-type semiconductor is given. Losses due to electron collisions are modeled by inclusion of the collision frequency ν_c in the relative permittivity tensor. Broadband low-loss operation of a semiconductor slotline junction circulator above the extraordinary wave resonance frequency f_res appears possible at near-millimetric frequencies. Larger, applied static magnetic fields enable narrowband low-loss operation at frequencies below the resonance at f_res. A 40-GHz design is described for GaAs cooled to 77 K. The minimum inband insertion loss is 0.82 dB. InSb theoretically possesses still lower losses for a reduced applied magnetic field. An example at an operating frequency of 75 GHz in InSb is given