المؤلفون: Liu, Jieyu, Liu, Wenjuan, Wen, Zhiwei, Tong, Xin, Liu, Yan, Cai, Yao, Sun, Chengliang

المصدر: Applied Physics Letters; 5/13/2024, Vol. 124 Issue 20, p1-5, 5p

مصطلحات موضوعية: ACOUSTIC resonators, SOUND waves, INTERDIGITAL transducers, PISTONS, SHEAR waves, LITHIUM niobate, ACOUSTIC wave propagation

مستخلص: Lateral-excited bulk acoustic wave resonators (XBARs) have a large electromechanical coupling coefficient and low mechanical loss. However, XBARs have not yet been commercialized in 5G communications due to spurious modes, high TCF, and low-power handling. This paper presents a lateral-excited bulk acoustic wave resonator with piston mode electrodes named PLBAR. Compared to the conventional interdigital transducer structure, the PLBAR suppresses the transverse waves due to the irregular boundary caused by piston mode electrodes. Higher order modes are also to some extent suppressed by increasing in metallization rate. The fabricated PLBAR achieves a high K eff 2 of 26.43% at 5.2 GHz using a 350 nm Z-cut lithium niobate on insulator substrate, effectively suppressing the transversal mode. Additionally, the power durability exceeds +14 dBm due to the increased metallization of the piston mode electrodes. The measured temperature coefficient of PLBAR is −42.55 ppm/°C. The PLBAR addresses some of the limitations of the XBARs and demonstrates significant improvements in performance without requiring additional fabrication steps, making it a promising solution for RF resonators in 5G communication systems. [ABSTRACT FROM AUTHOR]

: Copyright of Applied Physics Letters is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Wu, Lei¹ (AUTHOR), Pasini, Damiano¹ (AUTHOR) damiano.pasini@mcgill.ca

المصدر: Applied Physics Letters. 5/29/2023, Vol. 122 Issue 22, p1-5. 5p.

مصطلحات موضوعية: *ELASTIC wave propagation, *RESONANCE, *ELASTIC waves, *METAMATERIALS, *RESONATORS

مستخلص: We report a topology-transformable resonator with two distinct stable states, one kinematically determinate and endowed with nearly rigid-body motion at low-frequencies, and the other accompanied by a floppy pseudo zero-energy mode capable of showing low-frequency local resonance. Through a combination of numerical simulations and experiments, we unveil the role of contact-induced topological transformation, a phenomenon that empowers the resonator with negative dynamic effective mass. We demonstrate that the bistable resonator can be embedded into elastic metamaterials to enable in situ switch of local resonance, allowing on-demand augmentation and attenuation of elastic wave propagation within a prescribed regime of frequency. [ABSTRACT FROM AUTHOR]

المؤلفون: Wang, Yanan, Lee, Jaesung, Feng, Philip X.-L.

المصدر: Applied Physics Letters; 2/12/2024, Vol. 124 Issue 7, p1-13, 13p

مصطلحات موضوعية: GENETIC transduction, MECHANICAL oscillations, AUTOMATIC control systems, ACOUSTIC wave propagation, CELLULAR signal transduction, INTEGRATED circuits

مستخلص: Phononic waveguides (PnWGs) are devices with rationally designed periodic structures to manipulate mechanical oscillations and to engineer and control the propagation of acoustic waves, thus allowing for frequency and band selection of wave transmission and routing, promising for both classical and quantum transduction on chip-scale platforms with various constituent materials of interest. They can be incorporated into both electromechanical and optomechanical signal transduction schemes. Here, we present an overview of emerging micro/nanoscale PnWGs and offer perspectives for future. We evaluate the typical structural designs, frequency scaling, and phononic band structures of the PnWGs. Material choices, fabrication techniques, and characterization schemes are discussed based on different PnWG designs. For classical transduction schemes, an all-phononic integrated circuit perspective is proposed. Toward emerging quantum applications, the potential of utilizing PnWGs as universal interfaces and transduction channels has been examined. We envision PnWGs with extraordinary propagation properties, such as nonreciprocity and active tunability, can be realized with unconventional design strategies (e.g., inverse design) and advanced materials (e.g., van der Waals layered crystals), opening opportunities in both classical and quantum signal transduction schemes. [ABSTRACT FROM AUTHOR]

: Copyright of Applied Physics Letters is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Aguzzi, Giulia¹ (AUTHOR) aguzzi@ibk.baug.ethz.ch, Thomsen, Henrik R.¹ (AUTHOR), Hejazi Nooghabi, Aida¹ (AUTHOR), Wiltshaw, Richard² (AUTHOR), Craster, Richard V.^2,3,4 (AUTHOR), Chatzi, Eleni N.¹ (AUTHOR), Colombi, Andrea¹ (AUTHOR)

المصدر: Applied Physics Letters. 11/14/2022, Vol. 121 Issue 20, p1-8. 8p.

مصطلحات موضوعية: *ELASTIC waves, *ELASTIC wave propagation, *UNIT cell, *ELECTROSTATIC discharges, *ENERGY harvesting, *NUMERICAL analysis, *AFFINE transformations

مستخلص: We experimentally demonstrate the capability of architected plates, with a frame-like cellular structure, to inhibit the propagation of elastic flexural waves. By leveraging the octet topology as a unit cell to design the tested prototypes, a broad and easy-to-tune bandgap is experimentally generated. The experimental outcomes are supported by extensive numerical analyses based on 3D solid elements. Drawing from the underlying dynamic properties of the octet cell, we numerically propose a tailorable design with enhanced filtering capabilities. We transform the geometry of the original unit cell by applying a uniaxial scaling factor that, by breaking the in-plane symmetry of the structure, yields independently tuned struts and consequently multiple tunable bandgaps within the same cell. Our findings expand the spectrum of available numerical analyses on the octet lattice, taking it a significant step closer to its physical implementation. The ability of the octet lattice to control the propagation of flexural vibrations is significant within various applications in the mechanical and civil engineering domains, and we note such frame-like designs could lead to advancements in energy harvesting and vibration protection devices (e.g., lightweight and resonance-tunable absorbers). [ABSTRACT FROM AUTHOR]

المؤلفون: Yves, Simon¹ (AUTHOR), Peng, Yu-Gui¹ (AUTHOR), Alù, Andrea^1,2 (AUTHOR) aalu@gc.cuny.edu

المصدر: Applied Physics Letters. 9/19/2022, Vol. 121 Issue 12, p1-7. 7p.

مصطلحات موضوعية: *ACOUSTIC wave propagation, *WAVEGUIDES, *ELECTROMAGNETIC waves, *ACOUSTICS, *PHASE transitions

مستخلص: Acoustic metamaterials and metasurfaces have been explored in the past few years to realize a wide range of extreme responses for sound waves. As one remarkable phenomenon, extreme anisotropy and hyperbolic sound propagation are particularly challenging to realize compared to electromagnetic waves because of the scalar nature of airborne acoustics. In parallel, moiré superlattices and the rapidly expanding domain of twistronics have shown that large anisotropy combined with tailored geometrical rotations can enable tantalizing emerging phenomena, such as tailored phase transitions in metamaterials. Connecting these areas of research, here, we explore the realization of acoustic hyperbolic metasurfaces and their combination to drive topological phase transitions from hyperbolic to elliptic sound propagation. The transition point occurring at a specific rotation angle between two acoustic metasurfaces supports highly directional canalization of sound, opening exciting opportunities for twisted acoustics metasurfaces for robust surface wave guiding and steering. [ABSTRACT FROM AUTHOR]

المؤلفون: Koujok, A., Riveros, A., Rodrigues, D. R., Finocchio, G., Weiler, M., Hamadeh, A., Pirro, P.

المصدر: Applied Physics Letters; 9/25/2023, Vol. 123 Issue 13, p1-6, 6p

مصطلحات موضوعية: ACOUSTIC surface waves, VORTEX motion, SPHEROMAKS, ACOUSTIC resonance, ACOUSTIC wave propagation, MAGNETOSTRICTION

مستخلص: Finding new energy-efficient methods for exciting magnetization dynamics is one of the key challenges in magnonics. In this work, we present an approach to excite the gyrotropic dynamics of magnetic vortices through the phenomenon of inverse magnetostriction, also known as the Villari effect. We develop an analytical model based on the Thiele formalism that describes the gyrotropic motion of the vortex core including the energy contributions due to inverse magnetostriction. Based on this model, we predict excitations of the vortex core resonances by surface acoustic waves whose frequency is resonant with the frequency of the vortex core. We verify the model's prediction using micromagnetic simulations and show the dependence of the vortex core's oscillation radius on the surface acoustic wave amplitude and the static bias field. Our study contributes to the advancement of energy-efficient magnetic excitations by relying on voltage-induced driven dynamics, which is an alternative to conventional current-induced excitations. [ABSTRACT FROM AUTHOR]

: Copyright of Applied Physics Letters is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Rummel, Brian D., Miroshnik, Leonid, Li, Andrew B., Balakrishnan, Ganesh, Sinno, Talid, Han, Sang M.

المصدر: Applied Physics Letters; 8/21/2023, Vol. 123 Issue 8, p1-5, 5p

مصطلحات موضوعية: ACOUSTIC surface waves, WAVE analysis, GALLIUM arsenide, TRANSDUCERS, ACOUSTIC resonators, ACOUSTIC wave propagation

مستخلص: Interdigitated transducer devices may provide an advantageous platform to study stress-enhanced interfacial phenomena at elevated temperatures, and an appropriate device design requires a thorough understanding of temperature-dependent material properties. In this study, the scattering parameter response for a surface acoustic wave resonator is simulated using a frequency-domain finite element method from 20 to 177 ° C. Experimental device measurements are taken for the interdigitated transducer device fabricated on semi-insulating GaAs 100 oriented in the 110 direction, and the results are in good agreement with the simulation. Surface acoustic wave analysis provides the magnitude of bulk stress values and surface displacement over the experimental temperature range produced by a standing surface acoustic wave. The computational analysis combined with experimental verification suggests that such devices, when optimized for the maximum magnitude, can produce strain levels that could influence chemical potential associated with crystalline growth, atomic diffusion, and catalytic reactions. The modeling results demonstrate an interdigitated transducer's potential as an experimental platform to study the impact of strain on temperature-sensitive surface and bulk phenomena in piezoelectric materials. [ABSTRACT FROM AUTHOR]

: Copyright of Applied Physics Letters is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Dong, Daxing, Li, Weimian, Li, Xiao, Liu, Jiaqing, Liu, Youwen, Ji, Hongli, Xu, Yadong, Fu, Yangyang

المصدر: Applied Physics Letters; 8/14/2023, Vol. 123 Issue 7, p1-7, 7p

مصطلحات موضوعية: ACOUSTIC surface waves, ACOUSTIC waveguides, WAVEGUIDES, ACOUSTIC wave propagation, SURFACE waves (Seismic waves), FANO resonance, SOUND waves, BOUND states

مستخلص: In this work, we theoretically and experimentally demonstrate that effective trapping, guiding, and manipulation of sound waves can be realized in spoof-fluid-spoof acoustic waveguides with gradient index modulation. Empowered by the abundant mode evolution physics between propagation waves and spoof acoustic surface waves in the gradient waveguide structure, various functional sound propagation phenomena, including broadband transmission, broadband reflection, Fabry–Pérot resonances, and Fano resonances, are unveiled. The underlying principle stems from the interplay of various mechanisms composed of gradient mode conversion, high-order mode resonances, and symmetry-protected bound states in the continuum. These effects can be effectively modulated through the manipulation of the fluid gap and doped defects within the waveguide structure. Our findings can offer possibilities for manipulating sound waves in a versatile manner and holding significant potential for various acoustic applications such as sensing, filtering, insulation, and wavefront engineering. [ABSTRACT FROM AUTHOR]

: Copyright of Applied Physics Letters is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Liu, Chen, Zhang, Zhiwang, Liao, Danwei, Yue, Zichong, Ma, Chengrong, Cheng, Ying, Liu, Xiaojun

المصدر: Applied Physics Letters; 7/24/2023, Vol. 123 Issue 4, p1-6, 6p

مصطلحات موضوعية: TOPOLOGICAL insulators, CONDENSED matter physics, RAINBOWS, ACOUSTIC wave propagation, HELMHOLTZ resonators, SOUND waves, THEORY of wave motion

مستخلص: Over the recent decade, topological insulators, originating from the condensed matter physics, have resided at the frontier in the field of acoustics owing to their novel topological properties for manipulating robust wave propagation, which have also opened an intriguing landscape for potential applications. At the meantime, gradually slowing down acoustic waves with metamaterials allows temporary storage of sound, leading to the exploration of so-called trapped rainbow. However, most of the current studies are reported in a topological trivial context with complex structures, and it is hitherto still a challenge to obtain the high-efficient acoustic rainbow trapping effect in a straightforward setup. Here, we propose an acoustic gradient topological insulator in the one-dimensional system to realize a highly efficient rainbow trapping device. Based on the acoustic analogous Su–Schrieffer–Heeger model, we tune the eigenfrequencies of the topological interface states through modulating the neck widths of Helmholtz resonators. The experimentally measured pressure spectra clearly show that the proposed structure could tightly trap the broad-band sound waves at the target spatial positions. Our proposal may provide versatile possibilities for the design of topological acoustic devices. [ABSTRACT FROM AUTHOR]

: Copyright of Applied Physics Letters is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Deymier, Pierre A., Runge, Keith

المصدر: Applied Physics Letters; 7/3/2023, Vol. 123 Issue 1, p1-5, 5p

مصطلحات موضوعية: SOUND waves, ACOUSTIC devices, ELASTIC wave propagation, SUPERLATTICES, ELASTIC waves, SYMMETRY breaking

مستخلص: Static superlattices that do not break time-reversal symmetry can support robust topologically protected elastic waves with non-zero amplitude in the forward propagating direction but zero amplitude in the opposite direction. We form a prototypical acoustic wave device by sandwiching a finite superlattice that supports one-way propagating waves between input and detector layers. Compared to conventional elastic waves, topologically protected waves provide a significant benefit for reducing the return loss of the prototypical device. Superlattices supporting topologically protected acoustic waves provide attractive and disruptive solutions for designing the next-generation of low-loss acoustic wave devices for telecommunication or sensing. [ABSTRACT FROM AUTHOR]

: Copyright of Applied Physics Letters is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)