Acoustic Delay Line Research Articles

Void-Engineered Metamaterial Delay Line with Built-In Impedance Matching for Ultrasonic Applications

Metamaterials exhibit unique ultrasonic properties that are not always achievable with traditional materials. However, the structures and geometries needed to achieve such properties are often complex and difficult to obtain using common fabrication techniques. In the present research work, we report a novel metamaterial acoustic delay line with built-in impedance matching that is fabricated using a common 3D printer. Delay lines are commonly used in ultrasonic inspection when signals need to be separated in time for improved sensitivity. However, if the impedance of the delay line is not perfectly matched with those of both the sensor and the target medium, a strong standing wave develops in the delay line, leading to a lower energy transmission. The presented metamaterial delay line was designed to match the acoustic impedance at both the sensor and target medium interfaces. This was achieved by introducing graded engineered voids with different densities at both ends of the delay line. The measured impedances of the designed metamaterial samples show a good match with the theoretical predictions. The experimental test results with concrete samples show that the acoustic energy transmission is increased by 120% and the standing wave in the delay line is reduced by over a factor of 2 compared to a commercial delay line.

A Voltage-Controlled Surface Acoustic Wave Oscillator Based on Lithium Niobate on Sapphire Low-Loss Acoustic Delay Line.

In this work, we investigate, for the first time, a low phase noise and wide tuning range voltage-controlled surface acoustic wave oscillator (VCSO) based on a lithium niobate on sapphire (LNOS) low-loss acoustic delay line (ADL). The thin-film LN/SiO2 bilayer acoustic waveguide, together with the single-phase unidirectional transducer (SPUDT) design, is key to attaining low insertion loss (IL) by enhancing energy confinement and directionality. Based on a high-performance ADL with an IL of only 5.2 dB, a fractional bandwidth (FBW) of 5.38%, and a group delay of 110 ns, the VCSO is implemented by commercially available circuit components using a series-resonant topology. The LNOS ADL oscillator operates at 888 MHz, showcasing a low phase noise of -94.1 dBc/Hz at 1-kHz offset and a root-mean-square (rms) jitter of only 30.26 fs (integrated from 12 kHz to 20 MHz) while only consuming 16 mA of supply current. Featuring a wide frequency tuning range of 6630 ppm, the proposed VCSO is a promising low-noise, low-power, and high-frequency timing device for emerging applications.Index Terms- Acoustic delay line (ADL), jitter, lithium niobate (LN), oscillator, phase noise, surface acoustic wave (SAW), thin film.skiptabldblfloatfix.

Addressable superconductor integrated circuit memory from delay lines

Recent advances in logic schemes and fabrication processes have renewed interest in using superconductor electronics for energy-efficient computing and quantum control processors. However, scalable superconducting memory still poses a challenge. To address this issue, we present an alternative to approaches that solely emphasize storage cell miniaturization by exploiting the minimal attenuation and dispersion properties of superconducting passive transmission lines to develop a delay-line memory system. This fully superconducting design operates at speeds between 20 and 100 GHz, with ± 24% and ± 13% bias margins, respectively, and demonstrates data densities in the 10s of Mbit/cm2 with the MIT Lincoln Laboratory SC2 fabrication process. Additionally, the circulating nature of this design allows for minimal control circuitry, eliminates the need for data splitting and merging, and enables inexpensive implementations of sequential access and content-addressable memories. Further advances in fabrication processes suggest data densities of 100s of Mbit/cm2 and beyond.

Биосенсор на основе пленки Ленгмюра-Блоджетт с ферментом алкогольоксидазы

The work examined the sensor properties of a biofilm based on phospholipid molecules 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine with immobilized molecules of the enzyme alcohol oxidase to vapors of ethyl and isopropyl alcohols. The immobilization of alcohol oxidase enzyme molecules was carried out using a Langmuir monolayer process of phospholipid molecules. The sensor coating was obtained using the Langmuir-Schaeffer technology, in which the substrate is oriented parallel to the monolayer. The analysis of microimages of the film surface obtained by atomic force microscopy, allows to present of enzyme molecules in it was established. The study of the sensory properties of the formed coatings was carried out using acoustoelectronic technology. The presence of the enzyme in the sensor coating led to an increase in the amplitude and phase responses of the acoustic delay line when interacting with vapors of the detected substance. The maximum amplitude and phase responses were recorded when the film interacted with ethanol vapor and were 1.5 dB and 19°, respectively. The work showed that the formed sensor coating has selective sensitivity to ethanol vapor. This allows us to conclude that it is possible to use this sensor coating to create an acoustoelectronic ethanol biosensor. Increasing the sensitivity of such biosensors can be achieved by varying technological parameters such as the number of layers in the film, as well as the amount of immobilized enzyme in each layer.

Acousto-electric measurements at 2.5 GHz on graphene transferred onto YX128°-LiNbO3

Surface acoustic wave delay lines with an operational frequency of 2.5 GHz have been designed to measure the acousto-electric transport of carriers in graphene transferred onto YX128°-LiNbO3 piezoelectric substrate. The monolayer of graphene on LiNbO3 presented sheet resistance in the range of 733–1230 Ω/□ and ohmic contact resistance with gold of 1880 to 5200 Ωμm. The measurements with different interaction lengths on graphene bars have allowed the extraction of carrier absorption and mobility parameters from acousto-electric current. Graphene presented higher acousto-electronic interaction in the GHz range than previously reported values in the range of 100s MHz with carrier absorption losses of 109 m−1 and mobility for acoustically generated charges of 101 cm2V−1s−1.

Features of the Formation of Sensitive Films Based on Mycelium of Higher Fungi for Surface and Plate Acoustic Waves Gas Sensors.

A comparative analysis of the responses of two types of acoustic waves (surface SAW and plate APW) with close frequencies and the same type of waves (SAW) with different frequencies toward various liquid vapors (water, acetone, ethanol) was carried out in this paper. Two types of films based on mycelium of higher fungus Ganoderma lucidum (Curtis) P. Karst (G. lucidum) prepared by various methods were used as sensitive coatings. These films were based on G. lucidum mycelium ethanolic (48% v/v) homogenizate (MEGl) and extract (EGl). A film deposition procedure compatible with acoustic devices technology was developed. Various piezoelectric substrates (YX-LiNbO3, 128 YX-LiNbO3) were used for appropriate acoustic delay lines production. It was found that additional SAW and APW attenuation associated with the appearance of mycelium films on the surface of the acoustic waveguide is two times greater for MEGL than for EGL films in the frequency range of 20-80 MHz The changes in acoustic wave amplitude and phase due to vapor absorption were measured and compared with each other, taking into account the differences in geometry of the samples. It was found that the phase response of the SAW delay lines with EGL films is three times higher than one with the presence of MEGL films for water and ethanol vapors. The films used are demonstrated good reproducibility and long-term stability for at least 2 months. Based on the results obtained, it was concluded that MEGl film is not appropriate for use in high frequency SAW delay lines as a sensitive coating. However, both types of the films (MEGl and EGl) could be used as sensitive coatings for low frequency SAW and APW sensors based on corresponding delay lines. Additionally, it was found that the films used are not sensitive to acetone vapor. As a result of the work carried out, a technique for creating sensitive films based on the mycelium of higher fungi compatible with the planar technology of acoustoelectronic delay lines was developed. The possibility of using such films for the development of gas SAW and APW sensors was shown.

Gigahertz Acoustic Delay Lines in Lithium Niobate on Silicon Carbide With Propagation-Q of 11174

This work demonstrates gigahertz wideband acoustic delay lines (ADLs) with record-breaking propagation-Q using a thin-film X-cut lithium niobate on silicon carbide (LiNbO3-on-SiC) platform. Benefiting from the high bulk wave velocity and excellent mechanical <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{f}\times \text{Q}$ </tex-math></inline-formula> of SiC, the shear horizontal surface acoustic wave (SH-SAW) excited by unidirectional transducers propagates in the top-surface of LiNbO3-on-SiC with low acoustic loss. The zero power flow angle (PFA) of −3° to +Y axis is obtained through simulation analysis and experiment validation, which leads to acoustic wave transmission perpendicular to the electrodes. Oriented at zero PFA, the fabricated ADLs show scalable center frequencies from 1.19 GHz to 2.11 GHz, 3-dB fractional bandwidth ranging from 2.7% to 11.5%, and a record-high propagation-Q of 11174. The performance has shown the great potential of the LiNbO3-on-SiC acoustic platform for various signal processing applications.

Expansion of beam width in exposure and crystal structure beamline (BL09) of SAGA-LS and applications using expanded beams

In this study, for high-efficiency experiments of deep X-ray lithography, radiation mutation breeding, and X-ray topography, we expanded the beam width in the exposure and crystal structure beamline (BL09) using a synchrotron beam at the SAGA Light Source facility. BL09 was divided into a straight A-line for hard X-rays and a branch B-line for soft X-rays; however, we reconstructed the new BL09 as a single straight-line by unifying the A and B-lines. Vacuum components, such as a large beam shutter, large beryllium window, acoustic delay line, and monochromator chamber were newly located in the reconstructed BL09. A white (or monochromatic) beam can be switched by removing (or inserting) the monochromator into the beam path as needed. After the reconstruction, the widths of the white and monochromatic beams at the terminal of BL09 were expanded from 110 to 395 mm and from 70 to 128 mm, respectively. The expanded white beam has the width of the world-class in synchrotron radiation facilities. Furthermore, we demonstrated the effect of the expanded beams and improvement in the experimental efficiency through deep X-ray lithography, radiation mutation breeding, and X-ray topography. The use of expanded beams is also expected to lead to the fabrication of practicable fine-structures and provide a deeper understanding of defect structures.

Equivalent Circuit Models for SAW Delay Line Sensors

Surface acoustic wave (SAW) devices are widely used as high quality factor filters for telecommunications. In recent years they have been investigated as sensors, which calls for application-specific electronic systems that interact with them. To design such circuits, it is important to understand the peculiarities of the devices, which may be a barrier for system designers. In this work, we explore different models that can be simulated in any circuit simulation environment, facilitating the creation of systems that interact with SAW delay lines, devices in which a signal is delayed by a constant time between piezoelectric transducers. The equivalent circuits of acoustic delay lines can be divided in two categories: a lumped-element model, based on frequency-dependent impedances implemented through the Foster and Mittag-Leffler theorems, and a distributed-element model, based on transmission lines. We compare qualitative frequency and time-domain characteristics among these categories so their limitations are clear, with the lumped-element model not being usable in the time domain due to its singularity at the center frequency. We also describe the process of implementation to achieve the model, while proposing a simple circuit block that can be included to represent perturbations on the device, which allows adjusting of the model response to different perturbations. Our model is also suitable for tests in distinct liquid media, provided that the parallel capacitor is fitted accordingly to model the electromagnetic wave induced in the device.

Programmable Acoustic Delay-Line Enabled Low-Cost Photoacoustic Tomography System.

Photoacoustic tomography (PAT) is an emerging technology for biomedical imaging that combines the superiorities of high optical contrast and acoustic penetration. In the PAT system, more PA signals are preferred to be detected from full field of view to reconstruct the PA images with higher fidelity. However, the requirement for more PA signals' detection leads to more time consumption for single-channel scanning-based PAT system or higher cost of data acquisition (DAQ) module for an array-based PAT system. To address this issue, we proposed a programmable acoustic delay-line (PADL) module to reduce DAQ cost and accelerate imaging speed for PAT system. The module is based on bidirectional conversion between acoustic signals and electrical signals, including ultrasound transmission in between to provide sufficient time delay. The acoustic delay-line module achieves tens or hundreds of microseconds' delay for each channel and is controlled by a programmable control unit. In this work, it achieves to merge four inputs of PA signals into one output signal, which can be recovered into original four PA signals in the digital domain after DAQ. The imaging experiments of pencil leads embedded in agar phantom are conducted by the PAT system equipped with the proposed PADL module, which demonstrated its feasibility to reduce the cost of the PAT system. An in vivo study of human finger PAT imaging with delay-line module verified its feasibility for biomedical imaging applications.

Low Loss Al0.7Sc0.3N Thin Film Acoustic Delay Lines

reports novel aluminum scandium nitride (Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.7</sub> Sc <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.3</sub> N) thin film acoustic delay lines (ADLs). Low loss ADLs are implemented on sputtered Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.7</sub> Sc <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.3</sub> N thin film using cross-field excited single-phase unidirectional transducers (SPUDT), which generate S0 mode Lamb wave between two ports. ADLs are fabricated with up to 300 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> flat delay gap by optimized low stress Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.7</sub> Sc <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.3</sub> N thin film. A large electromechanical coupling factor ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$K^{ {2}}$ </tex-math></inline-formula> ) of 7.8% provided by approximately 1 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.7</sub> Sc <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.3</sub> N thin film allows for an overall improvement. Compared to implemented aluminum nitride (AlN) thin film counterparts, Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.7</sub> Sc <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.3</sub> N ADLs achieve remarkably lower insertion loss (IL), wide fractional bandwidth (FBW), and better impedance matching, featuring a minimum IL of 2.27 dB and a 3-dB FBW of 7.1% at approximately 780 MHz. The increase in relative permittivity due to Sc doping reduces the imaginary part of the matched network by 40%. For fundamental symmetric (S0) Lamb waves, a high group velocity of 8532 m/s, a propagation loss of 0.07 dB/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$ {\lambda }$ </tex-math></inline-formula> , and a propagation quality factor (Q) of 338 are extracted. Upon further development, scandium (Sc) doped AlScN thin films could enable CMOS-compatible piezoelectric acoustic platform for signal processing, sensing, and computing applications.

Design and Optimization of a Novel SAW Gyroscope Structure Based on Amplitude Modulation with 1-D Phononic Crystals.

Surface acoustic wave gyroscopes (SAWGs), as a kind of all-solid-state micro-electro-mechanical system (MEMS) gyroscopes, can work normally under extremely high-impact environmental conditions. Among the current SAWGs, amplitude-modulated gyroscopes (AMGs) are all based on the same gyro effect, which was proved weak, and their sensitivity and intensity of the output are both lower than frequency-modulated gyroscopes (FMGs). However, because FMGs need to process a series of frequency signals, their signal processing and circuits are far less straightforward and simple than AMGs. In order to own both high-sensitivity and simple signal processing, a novel surface acoustic traveling wave gyroscope based on amplitude modulation is proposed, using one-dimensional phononic crystals (PCs) in this paper. In view of its specific structure, the proposed gyroscope consists of a surface acoustic wave oscillator and a surface acoustic wave delay line within a one-dimensional phononic crystal with a high-Q defect mode. In this paper, the working principle is analyzed theoretically through the partial wave method (PWM), and the gyroscopes with different numbers of PCs are also designed and studied by using the finite element method (FEM) and multiphysics simulation. The research results demonstrate that under a 1 V oscillator voltage output, the higher sensitivity of −23.1 mV·(rad/s)−1 in the linear range from −8 rad/s to 8 rad/s is reached when the gyro with three PC walls, and the wider linear range from −15 rad/s to 17.5 rad/s with the sensitivity of −6.7 mV·(rad/s)−1 with only one PC wall. Compared with the existing AMGs using metal dots to enhance the gyro effect, the sensitivity of the proposed gyro is increased by 15 to 112 times, and the linear range is increased by 4.6 to 186 times, even without the enhancement of the metal dots.

Review of Research on Storage Development

The development of computer external storage has undergone the continuous change of perforated cassettes, tapes, floppy disks, hard disks, optical disks and flash disks. Internal memory has gone through the development of drum storage, Williams tube, mercury delay line, and magnetic core storage, until the emergence of semiconductor memory. Later RAM and ROM were born. RAM was divided into DRAM and SRAM. Due to its structure and cost advantages, DRAM has gradually developed into the widely used DDR series. At the same time, the low-power LPDDR series has also been advancing. At present, with the development of NVRAM technology, non-volatile random access memory with both internal and external storage functions is born. Dual-space storage based on NVRAM combines internal and external storage into one, and large capacity dual-space storage has become the development trend of storage.&#x0D;

A Photoacoustic Sensing Probe Based on Silicon Acoustic Delay Lines

In this paper, we report new photoacoustic sensing (PAS) probe design based on silicon acoustic delay lines (SADLs). It consists of an optical fiber for light delivery and two SADLs for detecting/relaying the generated PA signals to an outside receiving transducer. Ultrasound testing shows that acoustic signals can be transmitted along the SADLs with low loss up to 17~20 MHz. To improve the PA excitation efficiency, a beveled tip is formed at the distal end of the optical fiber to align the optical illumination region with the acoustic detection zone of the SADLs. New polymer micro linkers fabricated with high-resolution 3-D printing are used to maintain the mechanical stability and acoustic isolation within the probe assembly. For demonstration, a prototype SADL-PAS probe was designed and fabricated. Its PA sensing performance (e.g., sensitivity, linearity, and depth resolution) is characterized. Testing results show that the SADL-PAS probe provides superior sensitivity with considerable high-frequency improvement. Ex-vivo tests in the chicken breast are conducted to demonstrate the PA target detection in biological tissues.

Detection of x rays by a surface acoustic delay line in contact with a diamond crystal

In this study, we present proof of concept for an x-ray detector. The hybrid device consists of a synthetic single crystal diamond in mechanical contact with a piezoelectric lithium niobate surface acoustic wave (SAW) delay line. Upon x-ray irradiation, the diamond crystal experiences a change in conductivity, which, in turn, very sensitively influences the SAW transmission on the delay line. This change in SAW attenuation is directly used to monitor the x-ray beam intensity. The SAW attenuation shows a monotonic variation with dose rate D in the studied range between 100 and 1800 μGy/s. While the response time leaves room for further improvement, the SAW detection principle offers the unique possibility for wireless remote powering and sensing.

Low loss surface acoustic wave SAW devices based on Al1-xMxN (M=Cr, Y, Sc) thin films

In this work, the coupling-of-modes (COM) approach and P-matrix model are used to investigate the frequency response of a two-port surface acoustic wave SAW delay line based on piezoelectric AlN doped with transition metals. The elastic and piezoelectric properties of Al1-xMxN (M = Cr, Y, Sc) thin films are theoretically investigated using the density functional theory (DFT). The results revealed that doping with Cr at x = 25% increases the piezoelectric response up to 288% compared to pure AlN, which is better than results obtained by others transition metal (Sc, Y) dopants. The frequency response of a two-port SAW delay line IDT/Al1-xMxN (M = Cr, Y, Sc)/Si shows that increasing dopants (Cr, Y and Sc) concentration considerably enhances the insertion loss and causes a significant shift down in the operating frequency. The obtained results are helpful in the design and fabrication of acoustic sensors and resonators with improved performances.

Acoustical Slot Mode Sensor for the Rapid Coronaviruses Detection.

A method for the rapid detection of coronaviruses is presented on the example of the transmissible gastroenteritis virus (TGEV) directly in aqueous solutions with different conductivity. An acoustic sensor based on a slot wave in an acoustic delay line was used for the research. The addition of anti-TGEV antibodies (Abs) diluted in an aqueous solution led to a change in the depth and frequency of resonant peaks on the frequency dependence of the insertion loss of the sensor. The difference in the output parameters of the sensor before and after the biological interaction of the TGE virus in solutions with the specific antibodies allows drawing a conclusion about the presence/absence of the studied viruses in the analyzed solution. The possibility for virus detection in aqueous solutions with the conductivity of 1.9–900 μs/cm, as well as in the presence of the foreign viral particles, has been demonstrated. The analysis time did not exceed 10 min.

Surface acoustic wave vibration sensor as a seismometer

Possibility of designing a seismometer based on the surface acoustic wave vibration sensor was reported. For the analysis of its properties, a theoretical model of the sensor transducer as a cantilever plate with a surface acoustic wave delay line, loaded with a seismic mass was developed. Description of the sensor mechanical part was simplified to the one degree of freedom damped mass-spring system. An explicit dependence of the plate geometry and material parameters, as well as the seismic mass size on the sensor frequency response was obtained. On this basis, the examples of vibration sensors with resonance frequencies useful in seismometry were manufactured. Tests confirmed the sufficient accuracy of the model to design and analyze a seismometer with the required properties. The proposed seismometer design is quite simple and its parameters may be competitive in relation to the currently used solutions.

Gigahertz Phononic Integrated Circuits on Thin-Film Lithium Niobate on Sapphire

Acoustic devices play an important role in classical information processing. The slower speed and lower losses of mechanical waves enable compact and efficient elements for delaying, filtering, and storing of electric signals at radio and microwave frequencies. Discovering ways of better controlling the propagation of phonons on a chip is an important step towards enabling larger scale phononic circuits and systems. We present a platform, inspired by decades of advances in integrated photonics, that utilizes the strong piezoelectric effect in a thin film of lithium niobate on sapphire to excite guided acoustic waves immune from leakage into the bulk due to the phononic analogue of index-guiding. We demonstrate an efficient transducer matched to 50 ohm and guiding within a 1-micron wide mechanical waveguide as key building blocks of this platform. Putting these components together, we realize acoustic delay lines, racetrack resonators, and meander line waveguides for sensing applications. To evaluate the promise of this platform for emerging quantum technologies, we characterize losses at low temperature and measure quality factors on the order of 50,000 at 4 kelvin. Finally, we demonstrate phononic four-wave mixing in these circuits and measure the nonlinear coefficients to provide estimates of the power needed for relevant parametric processes.

Method of Determining the Elastic Characteristics of Graphene and Other 2D Nanoallotropes

To calculate and design nanoelectronic and nanophotonic devices, in which graphenes and graphene-like 2D nanoallotropes of carbon, silicon, and binary III–V compounds are used, knowledge of the elastic characteristics and piezoelectric, photoelastic, and other properties of 2D materials, which depend on them, is of great significance. In this work, a simple method suitable for engineering calculations of determining the isothermal values of the force constants, elastic rigidities, Young’s modulus, and Poisson coefficient for 2D nanoallotropes of elements of Group IV of the periodic table and binary III–V compounds is proposed. The method is based on the Harrison method of bonding orbitals modified by S.Yu. Davydov and the R. Keating model for describing the elastic properties of such materials. It is shown that the method makes it possible to perform evaluative calculations of the elastic properties for known synthesized 2D crystal structures as well as for structures “constructed” theoretically. It is established that single-layer hexagonal boron nitride and other binary III–V compounds in the form of 2D nanoallotropes of various types of symmetry, which are piezoelectrics in addition, can be promising materials for nanoelectronics along with graphene. This extends the spectrum of the possible practical applications of the studied 2D materials (C, Si, BN, AlN, GaN, AlP, and GaP) both with a graphene-like and more complex structure. The results of this work can be used when developing the acoustic delay lines of the terahertz-frequency range, piezoelectric transducers for exciting and receiving elastic waves in nanoscale 2D acoustic lines, as well as piezoelectric sensors.