Results 71 to 80 of about 13,645 (194)
Advanced Science, EarlyView.Terahertz resonances in crystalline heterostructures could close a spectral gap between conventional electronics and photonics while opening new windows on non‐equilibrium lattice dynamics. Femtosecond optical screening of the depolarization field in epitaxial PbTiO3/SrTiO3 superlattices launches a collective polar mode that oscillates near 1 THz and ...
Deepankar Sri Gyan +13 more
wiley +1 more source
Frontiers in Materials, 2023 Metamaterials are a group of materials/structures which possess novel behaviors not existing in nature. The metamaterials include electromagnetic metamaterials, acoustic metamaterials, mechanical metamaterials, etc.
Hao Wang +5 more
doaj +1 more source
, 2017 A novel design of an elastic metamaterial with anisotropic mass density is proposed to manipulate flexural waves at a subwavelength scale. The three-dimensional metamaterial is inspired by kirigami, which can be easily manufactured by cutting and folding
Huang, G. L. +3 more
core +2 more sources
Advanced Science, EarlyView.In this work, a bioinspired all‐in‐one underwater quality evaluation metamaterial, combining sound attenuation, diffuse reflection, and mechanical robustness, is proposed based on jumping spider locomotion and human skeletal biomechanics. Meanwhile, a CNN‑driven quality evaluation framework is established for theoretically dimension‐reduced ...
Hongze Li +8 more
wiley +1 more source
Menger fractal structure with negative refraction and sound tunnelling properties
Materials Research Express, 2019 We construct new quasi-three-dimensional fractal acoustic metamaterials based on adoption of the Menger structure, which offers extraordinary parameters such as double-negative properties and a near-zero density.
Yu Liu +6 more
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A Nonlinear Gradient-Coiling Metamaterial for Enhanced Acoustic Signal Sensing
Crystals, 2023 Acoustic sensing systems play a critical role in identifying and determining weak sound sources in various fields. In many fault warning and environmental monitoring processes, sound-based sensing techniques are highly valued for their information-rich ...
Guodong Hao, Xinsa Zhao, Jianning Han
doaj +1 more source
Active Metamaterials with Tunable Shear Nonreciprocity and Nonlinear Dynamics
Advanced Science, EarlyView.Active gear‐based mechanical metamaterials enable simultaneous control of translational and torsional stiffnesses by 30–100×, break shear reciprocity under positive versus negative loads, broadly tune resonant frequencies, and offer programmable dynamic responses.
Xin Fang, Miao Yu, Dianlong Yu, Li Cheng
wiley +1 more source
Modulating Sound with Acoustic Metafiber Bundles
Scientific Reports, 2017 Acoustic metamaterials and metasurfaces provide great flexibility for manipulating sound waves and promise unprecedented functionality, ranging from transformation acoustics, acoustic cloaking, acoustic imaging to acoustic rerouting.
Jian-ping Xia +2 more
doaj +1 more source
Scientific Reports, 2022 For three-dimensional pentamode metamaterials, it is of great significance to realize underwater low frequency acoustic wave control. Therefore, in order to compare with traditional double-cone pentamode metamaterials, two multilayer composite ...
Chengxin Cai +6 more
doaj +1 more source
Negative group velocity and three-wave mixing in dielectric crystals
, 2011 Extraordinary features of optical parametric amplification of Stokes electromagnetic waves are investigated, which originate from three-wave mixing of two ordinary electromagnetic and one backward phonon wave with negative group velocity.
Myslivets, Sergey A. +3 more
core +1 more source