Equivalent network representation in cylindrical coordinates for trapped-energy resonators operating in backward-wave-type thickness vibration modes

The authors presented a novel and unique technique of energy trapping applicable for thickness vibrations of backward-wave modes. A special arrangement of electrodes and introduction of a capacitance connected in series with the excitation electrodes enabled the creation of trapped-energy modes. Equivalent-network analysis clarified special energy trapping features. However, the network model used at that time was for one-dimensional analysis and was not applicable for widely used resonators having circular electrodes. As described herein, an equivalent network representation in cylindrical coordinates is presented for backward-wave-type trapped-energy resonators having circular electrodes. Distinguishing features of the trapped-energy resonator of backward-wave modes were reconfirmed.