H-Shaped Radial Phononic Crystal for High-Quality Factor on Lamb Wave Resonators

Abstract

In this paper, a novel H-shaped radial phononic crystal (H-RPC) structure is proposed to suppress the anchor loss of a Lamb wave resonator (LWR), which has an ultra-high frequency (UHF) and ultra-wideband gap characteristics. Compared to previous studies on phononic crystal (PC) structures aimed at suppressing anchor loss, the radial phononic crystal (RPC) structure is more suitable for suppressing the anchor loss of the LWR. By using the finite element method, through the research and analysis of the complex energy band and frequency response, it is found that the elastic wave can generate an ultra-wideband gap with a relative bandwidth of up to 80.2% in the UHF range when propagating in the H-RPC structure. Furthermore, the influence of geometric parameters on the ultra-wideband gap is analyzed. Then, the H-RPC structure is introduced into the LWR. Through the analysis of the resonant frequency, it is found that the LWR formed by the H-RPC structure can effectively reduce the vibration energy radiated by the anchor point. The anchor quality factor was increased by 505,560.4% compared with the conventional LWR. In addition, the analysis of the LWR under load shows that the LWR with the H-RPC structure can increase the load quality factor by 249.9% and reduce the insertion loss by 93.1%, while the electromechanical coupling coefficient is less affected.

An Investigation of the Energy Harvesting Capabilities of a Novel Three-Dimensional Super-Cell Phononic Crystal with a Local Resonance Structure

“…The structures investigated here stem from the physical mechanism of local resonance, which have an edge on traditional Bragg scatter types [ 12 , 13 , 14 , 15 ]. Typically, the BGs of Bragg scatter types generally have high frequencies.…”

Sandwich Plate Structure Periodically Attached by S-Shaped Oscillators for Low Frequency Ship Vibration Isolation

“…Phononic crystal [ 1 ] is an artificial periodic composite material/structure with an elastic wave band gap that has attracted extensive interest from scholars at home and abroad in recent years. Due to the elastic band gap characteristics [ 2 , 3 , 4 , 5 ] of the phononic crystal structure, vibration will be difficult to propagate in the corresponding band gap, so there are many potential applications in vibration and noise reduction [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ] that can be widely used in ships, aircraft, and other engineering fields. In existing studies, Bragg scattering [ 15 ] and local resonance [ 16 ] are the main mechanisms of band gap formation, between which locally resonant phononic crystals can generate low-frequency band gaps.…”

Multi-Material Radial Phononic Crystals to Improve the Quality Factor of Piezoelectric MEMS Resonators

“…Radial phononic crystals (RPCs) are cyclic structures periodically arranged along the radial direction based on cylindrical coordinate system, and they have complete band-gap characteristics [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. Torrent et al studied the propagation characteristics of body waves in RPCs and found that the propagation of body waves in specific frequency bands were prohibited, and they verified the band-gap characteristics [ 20 , 21 , 22 ].…”

“…The RPCs designed by the above researchers have excellently achieved isolating acoustic waves. In the field of MEMS resonators, He et al proposed an H-shaped RPC structure for a Lamb-wave resonator based on a cylindrical coordinate system [ 28 ], which generated a band gap and improved the Q of the resonator. Since the studied structure was a single material, this caused some strength damage to the resonator at the anchor point when etching the substrate, which resulted in poor stability of the structure.…”