المؤلفون: Xi, Feng, Tang, Yuxia, Hu, Li

المصدر: European Physical Journal B: Condensed Matter; Nov2023, Vol. 96 Issue 11, p1-8, 8p

مصطلحات موضوعية: PHONONIC crystals, CONDENSED matter physics, CRYSTAL lattices, ACOUSTIC wave propagation, PHASE transitions

مصطلحات جغرافية: SCHWABISCH Hall (Germany)

مستخلص: Valley topological edge state has been extended from condensed matter physics to acoustics and rapidly developed, in which one-way propagation in valley topological phononic crystal is achieved breaking the spatial reversal symmetry. Here, we present a 2D hexagonal lattice phononic crystal with the reconfigurable scatters composed of three rectangle rods. By rotating its three-legged rods, two distinct valley edge states can be realised and the valley Hall topological transition phase also is triggered. We numerically simulate the projected band structures of the supercells including zigzag and armchair interface and verify the existence of valley edge states. We demonstrate the acoustic topological transport in the straight interface and sharply curved path. Then, in an across-interface, acoustic splitting and emerging are also observed. Furthermore, we design the complicated interfaces constructed by phononic crystals with distinct valley Hall topological phase. We verify the chiral selective transports in the oriented interface if the excited point source positioned at different interfaces. The chiral selective valley topological propagation of acoustic wave provides many potential applications in designing acoustic switch, splitter and acoustic waveguide. [ABSTRACT FROM AUTHOR]

: Copyright of European Physical Journal B: Condensed Matter is the property of Springer Nature 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: Wang, Yuanbo, Dong, Yibao, Zhai, Shilong, Ding, Changlin, Luo, Chunrong, Zhao, Xiaopeng

المصدر: Journal of Applied Physics; 12/21/2020, Vol. 128 Issue 23, p1-9, 9p

مصطلحات موضوعية: CONDENSED matter physics, PHONONIC crystals, LATTICE constants, TOPOLOGICAL insulators, ACOUSTIC wave propagation, SOUND waves, PHOTOACOUSTIC spectroscopy

مستخلص: Topological insulators (TIs) in condensed matter physics have been rapidly developed in acoustic fields and have enabled the controlling of acoustic waves in brand new ways recently. The current acoustic analogs of electronic TIs are mainly based on sonic crystal Bragg scattering. The practical applications of these TIs were restricted by a non-adjustable geometric structure, a wavelength equivalent scale, and a high and fixed frequency response. Here, we propose subwavelength acoustic TIs on the basis of negative metamaterials, which utilize local resonance different from Bragg scattering to design topologically protected acoustic propagation. We demonstrate the existence of band inversion by altering the ratio of the distance of the meta-atoms to the lattice constant. More importantly, the dispersion and edge states of the Dirac cones can offer tunability within a wide frequency range under a fixed lattice constant by adjusting the structural parameters of the meta-atoms. Theoretical analysis, numerical simulations, and experimental measurement verify the edge states of the acoustic TIs. The proposed acoustic topological metamaterials provide a flexible way of manipulating sound propagation. [ABSTRACT FROM AUTHOR]

: Copyright of Journal of Applied Physics 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: Li, Runze, Du, Zhaodong, Qian, Xuejun, Li, Yan, Martinez-Camarillo, Juan-Carlos, Jiang, Laiming, Humayun, Mark S, Chen, Zhongping, Zhou, Qifa

المصدر: Quantitative Imaging in Medicine and Surgery. 11(3)

مصطلحات موضوعية: Engineering, Biomedical Engineering, Neurosciences, Rehabilitation, Eye Disease and Disorders of Vision, Clinical Research, Assistive Technology, Bioengineering, Eye, Optical coherence elastography, elastic wave propagation, mechanical shaker, retinal prosthetic electrode, Condensed Matter Physics, Optical Physics, Other Physical Sciences, Biomedical engineering, Atomic, molecular and optical physics

الوصف: BackgroundQuantitatively investigating the biomechanics of retina with a retinal prosthetic electrode, we explored the effects of the prosthetic electrode on the retina, and further supplemented data for a potential clinical trial.MethodsBiomechanical properties were assessed with a high resolution optical coherence tomography (OCT) based elastography (OCE) system. A shaker was used to initiate elastic waves and an OCT system was used to track axial displacement along with wave propagation. Rabbits received surgery to implant the retinal prosthetic electrode, and elastic wave speed was measured before and after implantation; anatomical B-mode images were also acquired.ResultsSpatial-temporal maps of each layer in retina with and without prosthetic electrodes were acquired. Elastic wave speed of nerve fiber to inner plexiform layer, inner nuclear to outer nuclear layer, retinal pigmented epithelium layer and choroid to sclera layer without prosthetic electrode were found to be 3.66±0.36, 5.33±0.07, 6.85±0.37, and 9.69±0.24 m/s, respectively. With prosthetic electrode, the elastic wave speed was found to be 4.09±0.26, 5.14±0.11, 6.88±0.70, and 9.99±0.73 m/s, respectively in each layer.ConclusionsOur results show that the elastic wave speed in each layer of retina is slightly faster with the retinal electrode, and further demonstrate that the retinal prosthetic electrode does not affect biomechanical properties significantly. In the future, we expect OCE technology to be used by clinicians where it could become part of routine testing and evaluation of the biomechanical properties of the retina in response to long term use of prosthetic electrodes in patients.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/1zf1z634Test

المؤلفون: Lapostolle, Lucas, Derrien, Katell, Morin, Léo, Berthe, Laurent, Castelnau, Olivier

المساهمون: Laboratoire Procédés et Ingénierie en Mécanique et Matériaux (PIMM), Conservatoire National des Arts et Métiers CNAM (CNAM), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies, HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM), ANR-18-CE08-0026,ForgeLaser,Traitement par Choc laser pour surfaces claustrées(2018)

المصدر: ISSN: 0020-7683 ; International Journal of Solids and Structures ; https://hal.science/hal-03591184Test ; International Journal of Solids and Structures, 2022, 239-240, pp.111422. ⟨10.1016/j.ijsolstr.2022.111422⟩.

مصطلحات موضوعية: Applied Mathematics, Mechanical Engineering, Mechanics of Materials, Condensed Matter Physics, General Materials Science, Modeling and Simulation, Laser shot peening, Elasto-plastic wave propagation, Homogenization, Laminate material, Numerical simulation, [SPI]Engineering Sciences [physics]

الوصف: International audience ; The aim of this paper is to study the effect of microstructure heterogeneity upon elasto-plastic wave propagation generated during laser shot peening. We consider a simplified elasto-plastic laminate specimen subjected to uniaxial strain. The microstructure is composed of two phases alternating periodically and perfectly bonded together. The associated PDE system is solved using a high-resolution Godunov scheme, allowing to study the wave propagation in the heterogeneous structure. It is found that, even for a small mechanical contrast between the two phases, the considered laminate microstructure has a significant effect on the distribution of plastic strain. In addition, an elasto-plastic homogenization of the laminate has been carried out, and the resulting Homogeneous Equivalent Medium (HEM) has been used to decrease the computation time of the wave propagation. The HEM-based model is able to reproduce accurately the full-field solution in terms of distribution of mean plastic strain within the specimen and its fluctuation between the two phases.

العلاقة: hal-03591184; https://hal.science/hal-03591184Test; https://hal.science/hal-03591184/documentTest; https://hal.science/hal-03591184/file/PIMM_IJSS_2022_LAPOSTOLLE.pdfTest

الإتاحة: https://doi.org/10.1016/j.ijsolstr.2022.111422Test
https://hal.science/hal-03591184Test
https://hal.science/hal-03591184/documentTest
https://hal.science/hal-03591184/file/PIMM_IJSS_2022_LAPOSTOLLE.pdfTest

المؤلفون: Francesca Fantoni, Andrea Bacigalupo, Giorgio Gnecco, Luigi Gambarotta

مصطلحات موضوعية: Beam lattice metamaterial, Damped wave propagation, Mechanics of Materials, Mechanical Engineering, Beam lattice metamaterial, Damped wave propagation, Complex-valued frequency spectrum, Gradient-based optimization, Dimensionality reduction, General Materials Science, Condensed Matter Physics, Complex-valued frequency spectrum, Dimensionality reduction, Civil and Structural Engineering, Gradient-based optimization

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b28b4d30f56e9d514a0bca5b256be6ebTest
https://hdl.handle.net/11567/1118604Test

المؤلفون: Hayran, Zeki, Hassani Gangaraj, Seyyed Ali, Monticone, Francesco

المصدر: Nanophotonics (21928606); Aug2019, Vol. 8 Issue 8, p1371-1378, 8p

مصطلحات موضوعية: CONDENSED matter physics, ELECTROMAGNETIC wave propagation, TOPOLOGICAL insulators, PLANE wavefronts, ROUTING algorithms, TOPOLOGICAL fields, PLASMONICS

مستخلص: Achieving robust propagation and guiding of electromagnetic waves through complex and disordered structures is a major goal of modern photonics research, for both classical and quantum applications. Although the realization of backscattering-free and disorder-immune guided waves has recently become possible through various photonic schemes inspired by topological insulators in condensed matter physics, the interaction between such topologically protected guided waves and free-space propagating waves remains mostly unexplored, especially in the context of scattering systems. Here, we theoretically demonstrate that free-space propagating plane waves can be efficiently coupled into topological one-way surface waves, which can seamlessly flow around sharp corners and electrically large barriers and release their energy back into free space in the form of leaky-wave radiation. We exploit this physical mechanism to realize topologically protected wave-rerouting around an electrically large impenetrable object of complex shape, with transmission efficiency exceeding 90%, over a relatively broad bandwidth. The proposed topological wave-rerouting scheme is based on a stratified structure composed of a topologically nontrivial magnetized plasmonic material coated by a suitable isotropic layer. Our results may open a new avenue in the field of topological photonics and electromagnetics, for applications that require engineered interactions between guided waves and free-space propagating waves, including for complex beam-routing systems and advanced stealth technology. More generally, our work may pave the way for robust defect/damage-immune scattering and radiating systems. [ABSTRACT FROM AUTHOR]

: Copyright of Nanophotonics (21928606) is the property of De Gruyter 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: Jean-Louis Izbicki, Bruno Morvan, P. Pareige, Damien Leduc

مصطلحات موضوعية: Materials science, Wave propagation, business.industry, Mechanical Engineering, Acoustics, Attenuation, Classical Physics (physics.class-ph), FOS: Physical sciences, Surface finish, Physics - Classical Physics, Condensed Matter Physics, symbols.namesake, Optics, Lamb waves, Surface metrology, Surface wave, symbols, General Materials Science, Phase velocity, Rayleigh wave, business, Physics::Atmospheric and Oceanic Physics

الوصف: This work deals with the sensitivity to the plate roughness of Lamb waves. An experimental study is performed involving an air-coupling transducer system. Signal processing allows us to extract the Lamb waves characteristics: phase velocity and attenuation. Plate surface topographies are obtained by means of an optical surface profiler. The acoustic characteristics and the surface topographies are finally linked.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a3708648ab3dc8c4ec1d90b5013ea656Test
http://arxiv.org/abs/2304.10393Test

المؤلفون: Gui-Lin She

المصدر: Journal of Thermal Stresses. 44:1289-1305

مصطلحات موضوعية: Materials science, Guided wave testing, Wave propagation, Thermal, Thermal effect, General Materials Science, Mechanics, Condensed Matter Physics, Porosity, Guided wave propagation

الوصف: Because there is no literature on the effect of thermal loadings on guided wave propagation in FG plates, the present paper is to fill the gap. In the present paper, the wave propagation analysis o...

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::5eb1e1d169ac1dcf674ce8de28cca50aTest
https://doi.org/10.1080/01495739.2021.1974323Test

المؤلفون: M. Mazzotti, A. Foehr, O.R. Bilal, A. Bergamini, F. Bosia, C. Daraio, N.M. Pugno, M. Miniaci

المساهمون: University of Colorado [Boulder], California Institute of Technology (CALTECH), University of Connecticut (UCONN), Swiss Federal Laboratories for Materials Science and Technology [Dübendorf] (EMPA), Politecnico di Torino = Polytechnic of Turin (Polito), Department of Applied Science and Technology [Politecnico di Torino] (DISAT), University of Trento [Trento], Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Université catholique de Lille (UCL)-Université catholique de Lille (UCL), Acoustique - IEMN (ACOUSTIQUE - IEMN), Université catholique de Lille (UCL)-Université catholique de Lille (UCL)-Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), M. Miniaci is supported by the EU H2020 ERC StG «POSEIDON», Grant Agreement No. 101039576.A. Bergamini, F. Bosia, N.M. Pugno, M. Miniaci are supported by the EU H2020 FET Open «BOHEME», Grant Agreement No. 863179.C. Daraio acknowledges financial support from the Department of Energy under grant DE-SC0021253., European Project: 101039576,Horizon Europe,ERC-2021-STG,POSEIDON(2022), European Project: 863179,H2020,H2020-FETOPEN-2018-2019-2020-01,BOHEME(2020), California Institute of Technology [CALTECH], University of Connecticut [UCONN], Swiss Federal Laboratories for Materials Science and Technology [Dübendorf] [EMPA], Politecnico di Torino = Polytechnic of Turin [Polito], Department of Applied Science and Technology [Politecnico di Torino] [DISAT], Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN], Acoustique - IEMN [ACOUSTIQUE - IEMN]

المصدر: International Journal of Mechanical Sciences
International Journal of Mechanical Sciences, 2023, 241, pp.107915. ⟨10.1016/j.ijmecsci.2022.107915⟩
International Journal of Mechanical Sciences, 241

مصطلحات موضوعية: Phononic crystals and metamaterials, Hierarchical structures, [SPI]Engineering Sciences [physics], Wave propagation, Mechanics of Materials, Mechanical Engineering, General Materials Science, Condensed Matter Physics, Civil and Structural Engineering

الوصف: Hierarchy provides unique opportunities for the design of advanced materials with superior properties that arise from architecture, rather than from constitutive material response. Contrary to the quasi-static regime, where the potential of hierarchy has been largely explored, its role in vibration mitigation and wave manipulation remains elusive. So far, the majority of the studies concerning hierarchical elastic metamaterials have proposed a self-similar repetition of a specific unit cell at multiple scale levels, leading to the activation of the same bandgap mechanism at different frequencies. On the contrary, here, we show that by designing non self-similar hierarchical geometries allows us to create periodic structures supporting multiple, highly attenuative and broadband bandgaps involving (independently or simultaneously) different scattering mechanisms, namely, Bragg scattering, local resonance and/or inertial amplification, at different frequencies. The type of band gap mechanism is identified and discussed by examining the vibrational mode shapes and the imaginary component of the wavenumber in the dispersion diagram of the unit cell. We also experimentally confirm this by performing measurements in the lowest frequency regime on a 3D printed structure. Hierarchical design strategies may find application in vibration mitigation for civil, aerospace and mechanical engineering.
International Journal of Mechanical Sciences, 241
ISSN:0020-7403

وصف الملف: application/octet-stream; application/application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::27c7362f825d371ea351afe26673f411Test
https://hdl.handle.net/11583/2973555Test