Figure 2
From: Center Frequency Stabilization in Planar Dual-Mode Resonators during Mode-Splitting Control
Examples where cuts cause different phenomena in a planar square resonator: (a) the unperturbed square with two orthogonal/uncoupled modes resonating simultaneously at f0; (b) a cut that perturbs each mode differently, being an electric cut for mode 1 and a magnetic cut for mode 2, removing mode degeneracy but maintaining overall mode orthogonality with no/low coupling (from local mode rotation) and no mode rotation/splitting; (c) similar to case (b) but with the cut’s position flipped with respect to the modes (feeds); and (d) a combination of cuts (b) and (c) where both coupling and mode splitting are observed due to the removed symmetry between the modes, which are now rotated by 45 degrees. The first mode’s frequency is denoted f1 or f′1, while the second’s is denoted f2 or f′2 (primes indicate rotated modes). The shown curves are qualitative, to indicate the characteristic behaviours under discussion.
