Theoretical investigation of the resonance properties of an active ring made of a ferrite-ferroelectric layered structure

A theoretical model of a microwave active ring resonator based on a ferrite-ferroelectric layered structure serving as a waveguide for hybrid electromagnetic-spin waves is developed. The resonator is made in the form of a closed ring consisting of a ferrite-ferroelectric delay line, a microwave amplifier, and a variable attenuator. The resonance properties of this system are studied theoretically. The feasibility is demonstrated of effectively controlling the resonance frequencies of the ring by varying the permittivity of the ferroelectric layer.