Designing a tunable acoustic resonator based on defect modes, stimulated by selectively biased PZT rods in a 2D phononic crystal

In this work, we investigate numerically the propagation of Lamb waves in a film bulk acoustic resonator (FBAR) structure formed by piezoelectric ZnO layer sandwiched between two Mo electrodes coupled with Bragg reflectors; the system is thus considered as a phononic-crystal (PnC) plate. The aim is to suppress the first-order symmetric Lamb wave mode considered as a spurious mode caused by the establishment of a lateral standing wave due to the reflection at the embedded lateral extremities of the structure; this spurious mode is superposing to the main longitudinal mode resonance of the FBAR. The finite element study, using harmonic and eigen-frequency analyses, is performed on the section of FBAR structure coupled with the PnC. In the presence of PnC, the simulation results show the evidence of a selective band gap where the parasitic mode is prohibited. The quality factor of the FBAR is enhanced by the introduction of the PnC. Indeed, the resonance and antiresonance frequencies passed from 1000 and 980 (without PnC) to 2350 and 1230 (with PnC), respectively. This is accompanied by a decrease in the electromechanical coupling coefficient from 10.60% to 6.61%.

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Continuous tuning of line defect modes in silicon two-dimensional phononic crystal

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/48/22/225102 ◽

2015 ◽

Vol 48 (22) ◽

pp. 225102 ◽

Cited By ~ 2

Author(s):

Duan Feng ◽

Dehui Xu ◽

Bin Xiong ◽

Yuelin Wang

Keyword(s):

Phononic Crystal ◽

Two Dimensional ◽

Line Defect ◽

Defect Modes ◽

Continuous Tuning

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Numerical Investigation of Phononic Crystal Based Film Bulk Acoustic Wave Resonators

Nanomaterials ◽

10.3390/nano11102547 ◽

2021 ◽

Vol 11 (10) ◽

pp. 2547

Author(s):

Linhao Shi ◽

Weipeng Xuan ◽

Biao Zhang ◽

Shurong Dong ◽

Hao Jin ◽

...

Keyword(s):

Acoustic Wave ◽

High Performance ◽

Phononic Crystal ◽

Acoustic Resonator ◽

Acoustic Energy ◽

Bulk Acoustic Wave ◽

Frequency Range ◽

Quality Factors ◽

Film Bulk ◽

Power Capability

Film bulk acoustic resonator (FBAR)-based filters have attracted great attention because they can be used to build high-performance RF filters with low cost and small device size. Generally, FBARs employ the air cavity and Bragg mirror to confine the acoustic energy within the piezoelectric layer, so as to achieve high quality factors and low insertion loss. Here, two-dimensional (2D) phononic crystals (PhCs) are proposed to be the acoustic energy reflection layer for an FBAR (PhC-FBAR). Four kinds of PhC structures are investigated, and their bandgap diagrams and acoustic wave reflection coefficients are analyzed using the finite element method (FEM). Then, the PhCs are used as the acoustic wave reflectors at the bottom of the piezoelectric stack, with high reflectivity for elastic waves in the specific frequency range. The results show that the specific PhC possesses a wide bandgap, which enables the PhC-FBAR to work at a broad frequency range. Furthermore, the impedance spectra of PhC-FBARs are very smooth with few spurious modes, and the quality factors are close to those of traditional FBARs with air cavities, showing the application potential of the PhC-FBAR filters with wide bandwidth and high power capability.

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SYMMETRY AND COUPLING EFFICIENCY OF THE DEFECT MODES IN TWO-DIMENSIONAL PHONONIC CRYSTALS

Modern Physics Letters B ◽

10.1142/s0217984907013754 ◽

2007 ◽

Vol 21 (22) ◽

pp. 1479-1488 ◽

Cited By ~ 7

Author(s):

Y. J. CAO ◽

Y. Z. LI

Keyword(s):

Phononic Crystal ◽

Plane Waves ◽

Coupling Efficiency ◽

Phononic Crystals ◽

Two Dimensional ◽

Defect Modes ◽

Transmission Coefficients ◽

Resonant Modes ◽

Incident Plane ◽

Match Theory

We study theoretically the symmetric property and coupling efficiency of the defect modes in a two-dimensional phononic crystal by calculating band structures, field distributions and transmission coefficients of the defect modes. The results show that the point defect could act as a microcavity surrounded by the phononic crystal, and the confining ability of the phononic crystal to the resonant modes strongly depends on the thickness of the phononic crystal. By investigating the transmission spectra, we also find that the defect modes cannot be absolutely excited by the normally incident plane waves. The transmission coefficients are calculated by using the eigen-mode match theory method under the supercell technique, which is applied to the phononic crystals with the defects for the first time.

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A phononic crystal coupled to a transmission line via an artificial atom

Communications Physics ◽

10.1038/s42005-020-00475-2 ◽

2020 ◽

Vol 3 (1) ◽

Author(s):

Aleksey N. Bolgar ◽

Daniil D. Kirichenko ◽

Rais. S. Shaikhaidarov ◽

Shtefan V. Sanduleanu ◽

Alexander V. Semenov ◽

...

Keyword(s):

Transmission Line ◽

Electromagnetic Waves ◽

Degrees Of Freedom ◽

Phononic Crystal ◽

Acoustic Resonator ◽

Acoustic Resonators ◽

Object A ◽

Artificial Atom ◽

Main Challenge ◽

Quantum Acoustics

Abstract The interaction of superconducting qubits with surface acoustic wave resonators in quantum regime has been achieved recently. It opens a new field of research – quantum acoustodynamics – and allows developing new types of quantum devices. The main challenge in this direction is to manufacture acoustic resonators in the gigahertz range. Here, we demonstrate that the structure of a hybrid acoustodynamic device can be significantly simplified, if we replace an acoustic resonator with a phononic crystal. Our crystal consists of narrow metallic stripes on a quartz surface. The artificial atom in turn interacts with a microwave transmission line. Therefore, two degrees of freedom of different nature, acoustic and electromagnetic, are coupled with a single quantum object. A scattering spectrum of propagating electromagnetic waves on the artificial atom visualizes acoustic modes of the phononic crystal. Our geometry allows realizing effects of quantum acoustics on a simple and compact system.

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