Article
Physics, Applied
Han Zhou, Amr Baz
Summary: This article presents a class of active nonreciprocal metamaterial (ANMM) that achieves acoustic nonreciprocity by employing a spatiotemporal modulation strategy on diaphragms in an acoustic duct. The proposed ANMM stands out from previous methods by introducing actively tunable space-time modulated feedback gain of the controllers. Numerical analysis and experiments demonstrate the nonreciprocal behavior of this material.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Applied
S. Tessier Brothelande, C. Croenne, F. Allein, J. O. Vasseur, M. Amberg, F. Giraud, B. Dubus
Summary: This study presents a nonreciprocal system consisting of a one-dimensional piezoelectric phononic crystal whose periodic electrical conditions are modulated in time. One-way longitudinal wave propagation is experimentally studied and compared to finite element temporal simulations. The experiments demonstrate the linear evolution and progressive closure of the central position of the bandgaps with the increase in modulation speed.
APPLIED PHYSICS LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Alok Ghanekar, Jiahui Wang, Cheng Guo, Shanhui Fan, Michelle L. Povinelli
Summary: We propose a nonreciprocal thermal emitter based on the dynamic modulation of graphene. By designing a graphene ribbon grating on a dielectric slab, high-quality resonances can be excited in the long-IR region. Upon modulation of the Fermi energy of graphene, asymmetric modal splitting results in large nonreciprocity, violating Kirchhoff's law of thermal radiation.
Article
Engineering, Mechanical
Ganesh U. Patil, Songyuan Cui, Kathryn H. Matlack
Summary: This study designs a phononic diode that can control the frequency, mode, and direction of nonreciprocal wave propagation by exploiting the mixing of double-frequency waves in nonlinear phononic materials. The dispersion branch associated with the nonreciprocal wave can be tuned by controlling the frequency of the pump waves, allowing nonreciprocal wave propagation at different frequencies. By selecting appropriate frequencies and controlling the band gaps through external precompression, switching between reciprocal and nonreciprocal wave propagation is possible.
EXTREME MECHANICS LETTERS
(2022)
Article
Physics, Applied
D. Psiachos, M. M. Sigalas
Summary: The study found that in subwavelength-dimensioned phononic crystals with large band gaps, the concept of band gap is destroyed when the radius of cylinders periodically placed inside a matrix of highly contrasting elastic properties varies with time. However, with the appropriate tuning of parameters, some band-gap region can be retained, making such systems possible candidates for tunable bandpass filters or phononic isolators, suitable for sensor applications.
PHYSICAL REVIEW APPLIED
(2021)
Article
Engineering, Mechanical
Soroush Sepehri, Mahmoud Mosavi Mashhadi, Mir Masoud Seyyed Fakhrabadi
Summary: Thanks to their extraordinary dynamic characteristics, nonlinear phononic crystals (PCs) have found invaluable academic and industrial significance, in recent years. In this paper, we investigate the roton-like behavior of PCs by introducing a nonlinear monoatomic chain with the third-neighbor interactions able to exhibit backward energy flow in the Brillouin zone. The results reveal that the roton-like behavior can lead to extraordinary characteristics in PCs and including nonlinearity can provide an extra level of control over their behavior.
NONLINEAR DYNAMICS
(2023)
Article
Physics, Fluids & Plasmas
B. L. Kim, C. Chong, S. Hajarolasvadi, Y. Wang, C. Daraio
Summary: In this study, the response of a one-dimensional phononic lattice with time-periodic elastic properties is investigated in both linear and nonlinear regimes using experimental, numerical and theoretical approaches. It is found that wave-number band gaps emerge under small-amplitude excitation, while large-amplitude responses are stabilized via the nonlinear nature of the magnetic interactions, resulting in a family of nonlinear time-periodic states. Controlling acoustic and elastic wave propagation by balancing nonlinearity and external modulation offers potential applications in signal processing and telecommunication devices.
Article
Physics, Applied
M. Moghaddaszadeh, M. A. Attarzadeh, A. Aref, M. Nouh
Summary: Unraveling real eigenfrequencies in non-Hermitian PT-symmetric Hamiltonians has opened new avenues in various fields. In this study, we investigate the wave propagation behavior of a one-dimensional non-Hermitian elastic medium with a universal complex stiffness modulation. We analyze the onset of complex conjugate eigenfrequencies and the existence conditions for wave-number gaps, and demonstrate the coalescence of multiple Bloch-wave modes at exceptional points.
PHYSICAL REVIEW APPLIED
(2022)
Article
Materials Science, Multidisciplinary
Vinicius F. Dal Poggetto, Federico Bosia, Marco Miniaci, Nicola M. Pugno
Summary: Spider orb webs are versatile structures optimized for prey capture and transmitting vibrations. By varying geometric characteristics and adding localized masses, the vibration spectrum of spider web geometry can be tailored to manipulate wave modes, resulting in wide complete band gaps in two-dimensional phononic crystals.
MATERIALS & DESIGN
(2021)
Article
Computer Science, Interdisciplinary Applications
Sergey I. Fomenko, Mikhail V. Golub, Olga V. Doroshenko, Yanzheng Wang, Chuanzeng Zhang
Summary: This paper presents an extended and advanced boundary integral equation method for simulating elastic wave excitation and propagation in layered piezoelectric phononic crystals with crack or electrode. The method demonstrates high accuracy and efficiency for comprehensive parametric analysis in complex cases.
JOURNAL OF COMPUTATIONAL PHYSICS
(2021)
Article
Acoustics
Javier Redondo, Luis Godinho, Kestutis Staliunas, Juan Vicente Sanchez-Perez
Summary: The design and development of advanced devices based on metamaterials to control the transmission of acoustic waves is a hot topic. An important class of these metamaterials is based on phononic crystals with Locally Resonant Structure, included in those commonly known as Locally Resonant Sonic Materials. The authors develop a comprehensive numerical model of periodic arrays of Hemholtz resonators, which explains in detail the physical mechanisms of destructive interference and allows the reproduction of the consequences of the interference. The numerical results are supported by experimental tests.
Article
Acoustics
N. Kherraz, M. Radzienski, M. Mazzotti, P. Kudela, F. Bosia, A. S. Gliozzi, D. Misseroni, N. M. Pugno, W. Ostachowicz, M. Miniaci
Summary: Research on phononic crystal structures has led to many interesting designs, but not all are convenient for practical applications. This study proposes a new design for a phononic crystal and uses a combined numerical-experimental procedure to characterize its dynamic behavior and verify wave filtering properties in wave propagation experiments. The outlined procedure aims to standardize metamaterial development and validation procedures.
JOURNAL OF SOUND AND VIBRATION
(2021)
Article
Acoustics
Hao Gao, Yegao Qu, Guang Meng
Summary: Phononic crystals are engineered structures with unique acoustic properties that cannot be found in natural materials. These crystals exhibit band gaps where wave propagation is prohibited due to their periodic structure. This article presents a method using a generalized plane wave expansion and voxel-based discretization to calculate the band structures of three-dimensional phononic crystals. The proposed method, integrated with an adaptive genetic algorithm, is used for topological optimization of constituent distribution to maximize the width of the band gap. Numerical results validate the effectiveness of the method for optimizing a cubic phononic crystal, and the eigenmodes of the optimized crystal are investigated to better understand the mechanism of band gap broadening.
JOURNAL OF VIBRATION AND ACOUSTICS-TRANSACTIONS OF THE ASME
(2023)
Article
Chemistry, Analytical
Fei Ge, Liye Zhao, Yang Zhang
Summary: A novel surface acoustic traveling wave gyroscope based on amplitude modulation using one-dimensional phononic crystals is proposed to achieve both high-sensitivity and simple signal processing. The theoretical analysis and finite element method design research demonstrate the higher sensitivity and wider linear range of the proposed gyroscope under specific structure.
Article
Mechanics
Shaowu Ning, Dongyang Chu, Fengyuan Yang, Heng Jiang, Zhanli Liu, Zhuo Zhuang
Summary: The research focuses on designing tunable phononic crystals to manipulate the band structures and directionality of wave propagation through applied deformation. By activating tunable factors like coupling effects, geometric and material nonlinearities, and scatterer rearrangement, the dynamic responses of PnCs can be adjusted. The study reveals that the strong coupling effect between matrix holes and scatterer, as well as geometric nonlinearity and scatterer rearrangement induced by deformation, play crucial roles in tuning band gaps and wave propagation directionality in PnCs.
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2021)
Article
Physics, Applied
H. Al Ba'ba'a, S. Nandi, T. Singh, M. Nouh
JOURNAL OF APPLIED PHYSICS
(2020)
Article
Multidisciplinary Sciences
Yong Hu, Zipeng Guo, Andrew Ragonese, Taishan Zhu, Saurabh Khuje, Changning Li, Jeffrey C. Grossman, Chi Zhou, Mostafa Nouh, Shenqiang Ren
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2020)
Article
Acoustics
A. Ragonese, M. Nouh
Summary: This paper investigates methods of band gap formation in two-dimensional locally resonant elastic metamaterials and proposes a technique for computing such gaps. By analyzing mode shapes associated with the deformation of unit cells, it is found that Bloch modes at the bounds of the first local resonance band gap have similar characteristics.
Article
Acoustics
Jesse Callanan, Rayhaan Iqbal, Revant Adlakha, Amir Behjat, Souma Chowdhury, Mostafa Nouh
Summary: Unmanned aerial vehicles, specifically quadrotor drones, are becoming more common in community and workplace settings, being utilized for photography, cinematography, and small parcel transport. Understanding the acoustic characteristics of quadrotor drones is essential, and this study quantitatively describes their acoustic signature by experimentally measuring the spatial acoustic pressure distribution. A physics-infused machine learning model is used to visualize and interpret the experimental results, aiming to inform future experiments and provide quantitative information on the acoustic near-field signature of quadrotor drones.
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2021)
Article
Physics, Applied
M. Moghaddaszadeh, R. Adlakha, M. A. Attarzadeh, A. Aref, M. Nouh
Summary: Beam forming using phased arrays is fundamental to various sonar communication and biomedical imaging techniques. However, current arrays are limited by wave reciprocity and operational frequencies, hindering advancements in the field. The study presents nonreciprocal phased arrays that operate independently in different directions and frequency channels, offering enhanced capabilities in guided wave engineering. This system utilizes transceiving piezoelectric wafer discs bonded to an elastic medium with dynamic modulation, allowing concurrent phononic transitions in energy and momentum spaces to overcome Lorentz reciprocity constraints. The experimental demonstration validates the theoretical analysis of the array and its capabilities.
PHYSICAL REVIEW APPLIED
(2021)
Editorial Material
Crystallography
Mostafa Nouh, William J. Parnell, Mahmoud I. Hussein
Article
Instruments & Instrumentation
J. Callanan, C. L. Willey, V. W. Chen, J. Liu, M. Nouh, A. T. Juhl
Summary: A new class of electromechanically coupled metamaterial is introduced, which can realize vibration control through magnetic field interactions and exhibit a highly tunable vibration band gap with adjustable resonant circuit parameters.
SMART MATERIALS AND STRUCTURES
(2022)
Article
Engineering, Multidisciplinary
Abdulaziz Aladwani, Mostafa Nouh, Mahmoud I. Hussein
Summary: This paper generalizes the Bloch mode synthesis (BMS) approach using state-space transformation to extend its applicability to generally damped periodic materials. The study examines mode-selection schemes for non-classically damped periodic models and demonstrates the trade-offs between accuracy and efficiency.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Acoustics
A. Stein, M. Nouh, T. Singh
Summary: This paper investigates the behavior of acoustic metamaterials with multiple resonating elements, showing how different configurations of resonators can be used to expand the frequency range of band gaps, enabling a wider range of wave propagation profiles. The study develops analytical expressions for multi-resonator metamaterials, revealing the mechanisms behind band gap widening and dispersion transitions in parallel resonator metamaterials, as well as the potential for collapsing solutions of acoustic and optical bands in metamaterials with dual-periodic super cells.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Mechanics
A. Aladwani, A. Mohammed, M. Nouh
Summary: Elastic metamaterials offer transformative solutions in structural mechanics by exploiting their unique capabilities in wave propagation and control. This study comprehensively analyzes the influence of different configurations of a hierarchical mechanical network on the response, bandgap characteristics, and emergent dissipation. The authors demonstrate the significant roles played by network components, architecture, and damping placement using examples of locally resonant flexural beams. The presented framework enables a direct comparison with finite metamaterial counterparts and provides insights for tailoring efficient damped responses for specific applications.
Article
Physics, Applied
M. Moghaddaszadeh, M. A. Attarzadeh, A. Aref, M. Nouh
Summary: Unraveling real eigenfrequencies in non-Hermitian PT-symmetric Hamiltonians has opened new avenues in various fields. In this study, we investigate the wave propagation behavior of a one-dimensional non-Hermitian elastic medium with a universal complex stiffness modulation. We analyze the onset of complex conjugate eigenfrequencies and the existence conditions for wave-number gaps, and demonstrate the coalescence of multiple Bloch-wave modes at exceptional points.
PHYSICAL REVIEW APPLIED
(2022)
Article
Acoustics
Revant Adlakha, Wansong Liu, Souma Chowdhury, Minghui Zheng, Mostafa Nouh
Summary: This work presents a framework for mitigating the adverse effects of high-amplitude drone noise in human-robot collaborative environments by incorporating acoustic awareness into a path planning algorithm. The proposed approach reduces noise levels perceived by human workers and ensures compliance with industrial/environmental standards through the generation of optimal paths and a path-correction mechanism. Numerical simulations were conducted to verify the presented concepts.
JOURNAL OF VIBRATION AND CONTROL
(2022)
Article
Multidisciplinary Sciences
Hasan B. B. Al Ba'ba'a, Carson L. Willey, Vincent W. W. Chen, Abigail T. Juhl, Mostafa Nouh
Summary: This paper investigates the vibrational spectrum of finite phononic crystals in the form of one-dimensional rods and explains the factors that contribute to the origination of truncation resonances. By identifying a unit cell symmetry parameter, a family of finite phononic rods is defined. A transfer matrix method is utilized to derive closed-form expressions of the characteristic equations governing the natural frequencies and decipher the truncation resonances. This study establishes concrete connections between the localized vibrations, boundary conditions, and the configuration of the truncated chain, providing tools for predicting, tuning, and selectively designing truncation resonances.
ADVANCED THEORY AND SIMULATIONS
(2023)
Article
Instruments & Instrumentation
R. Adlakha, M. Nouh
Summary: In this paper, a class of non-Hermitian phased arrays is proposed to achieve selective directional suppression of harmonics by adjusting the amplitude modulation using gain, loss, and coupling between components. An experimental prototype is constructed to demonstrate the capability of selective directional suppression. The theory and experimental realization of non-Hermitian phased arrays provide new opportunities for precise elastoacoustic wave manipulation in various engineering applications.
SMART MATERIALS AND STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Mohammadreza Moghaddaszadeh, Andrew Ragonese, Yong Hu, Zipeng Guo, Amjad Aref, Chi Zhou, Shenqiang Ren, Mostafa Nouh
Summary: This study presents an experimental framework for controlling local resonance bandgap in a magnetically programmable metamaterial based on magnetorheological elastomers. The alignment of ferromagnetic particles under an external magnetic field enhances the sensitivity of the metamaterial's elastic modulus, allowing for control of the dispersive dynamics and shifting of the resonance-based bandgap. Numerical simulations also project the performance of the magnetically-tunable metamaterial at higher magnetic fields and levels of material anisotropy.
COMMUNICATIONS MATERIALS
(2023)
