The use of a thin vacuum-deposited InSb film as a K-band field displacement isolator

Room temperature measurements were taken at 23.9 GHz on an isolator fabricated by placing a 1-µm vacuum-deposited recrystallized thin film of InSb in K-band waveguide with the plane of the film parallel to the electric field and with an external magnetic field applied normal to the film (the field displacement mode). The best case gave an insertion loss of 7.4 dB, nonreciprocity of 13 dB, and isolation of 20.5 dB in an external magnetic field of 20 kOe.