Title :

Broadband sub-diffraction and ultra-high energy density focusing of elastic waves in planar gradient-index lenses

Author(s) :

Zhao, Jinfeng [Auteur]
Tongji University
Cui, Xiaodong [Auteur]
Tongji University
Bonello, Bernard [Auteur]
Institut des Nanosciences de Paris [INSP]
Djafari-Rouhani, Bahram [Auteur]
Physique - IEMN [PHYSIQUE - IEMN]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Yuan, Weitao [Auteur]
Tongji University
Pan, Yongdong [Auteur]
Tongji University
Ren, Jie [Auteur]
Tongji University
Zhang, Xiaoqing [Auteur]
Tongji University
Zhong, Zheng [Auteur]
Tongji University

Journal title :

Journal of the Mechanics and Physics of Solids

Pages :

104357

Publisher :

Elsevier

Publication date :

2021-05

ISSN :

0022-5096

English keyword(s) :

Gradient-index lens
Sub-diffraction focusing
Metamaterials
Energy harvesting

HAL domain(s) :

Sciences de l'ingénieur [physics]/Micro et nanotechnologies/Microélectronique

English abstract : [en]

We demonstrate experimentally and theoretically the broadband sub-diffraction and ultra-high energy density focusing of elastic wave inside planar gradient-index (GRIN) plate lenses based on thickness variation. The full ...
Show more >We demonstrate experimentally and theoretically the broadband sub-diffraction and ultra-high energy density focusing of elastic wave inside planar gradient-index (GRIN) plate lenses based on thickness variation. The full width at half maximum is ~0.40 times the minimum wavelength inside the lens λ0 or ~1/11 times the incident wavelength in the background plate λB. We analytically elucidate the underlying physical mechanism as the rapid oscillations in the propagator function at the focal distance. Our design displays several advantages including the broadband sub-diffraction behavior, three-order of magnitudes higher energy intensity at the focal point, and focusing capacity with a narrow transverse width of the lens, over the usual metastructure and/or phononic crystal based GRIN lenses. The broadband sub-diffraction and ultra-high energy density focusing can be used for energy harvesting and signal sensing.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Collections :

• Institut d'Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520

Source :

Harvested from HAL