A circulator for a waveguide is provided. The circulator comprises a waveguide housing including a central cavity, and a ferrite element disposed in the central cavity of the waveguide housing, with the ferrite element including a first surface and an opposing second surface. The circulator also comprises a pair of asymmetric dielectric spacers including a first dielectric spacer located on the first surface of the ferrite element, and a second dielectric spacer located on the second surface of the ferrite element.