359 citations · 862 across the 14 of their papers we have counts for
14 papers
Single-sensor and real-time ultrasonic imaging using an AI-driven disordered metasurface
Wei Wang, Jie Hu, Jingjing Liu +5
Non-destructive testing and medical diagnostic techniques using ultrasound has become indispensable in evaluating the state of materials or imaging the internal human body, respect…
Anomalous topological edge states in non-Hermitian piezophononic media
Penglin Gao, Morten Willatzen, Johan Christensen
The bulk-boundary or bulk-edge correspondence is a principle relating surface confined states to the topological classification of the bulk. By combining non-Hermitian ingredients…
Corner states in second-order mechanical topological insulator
Chun-Wei Chen, Rajesh Chaunsali, Johan Christensen +2
We numerically and experimentally study corner states in a continuous elastic plate with em-bedded bolts in a hexagonal pattern. While preserving C6 crystalline symmetry, the syste…
Flat bands in magic-angle vibrating plates
María Rosendo, Fernando Peñaranda, Johan Christensen +1
Twisted bilayer graphene develop quasi-flat bands at specific "magic" interlayer rotation angles through an unconventional mechanism connected to carrier chirality. Quasi-flat band…
Topological sound pumping of zero-dimensional bound states
Penglin Gao, Johan Christensen
Topological phases have spurred unprecedented abilities for sound, light and matter engineering and recent progress has shown how waves not only confine at the interfaces between t…
Majorana-like zero modes in Kekulé distorted sonic lattices
Penglin Gao, Daniel Torrent, Francisco Cevera +3
Topological phases have recently been realised in bosonic systems. The associated boundary modes between regions of distinct topology have been used to demonstrate robust waveguidi…
Ultrasonic nodal chains in topological granular metamaterials
Aurelien Merkel, Johan Christensen
Three-dimensional (3D) Weyl and Dirac semimetals garner considerable attention in condensed matter physics due to the exploration of entirely new topological phases and related unc…
Mechanical analogue of a Majorana bound state
Chun-Wei Chen, Natalia Lera, Rajesh Chaunsali +5
The discovery of topologically non-trivial electronic systems has opened a new age in condensed matter research. From topological insulators to topological superconductors and Weyl…
Valley Hall phases in Kagome lattices
Natalia Lera, Daniel Torrent, Pablo San-Jose +2
We report the finding of the analogous valley Hall effect in phononic systems arising from mirror symmetry breaking, in addition to spatial inversion symmetry breaking. We study to…
Ultrathin acoustic parity-time symmetric metasurface cloak
Hao-Xiang Li, Maria Rosendo-Lopez, Yi-Fan Zhu +5
Invisibility or unhearability cloaks have been made possible by using metamaterials making light or sound flow around obstacle without the trace of reflections or shadows. Metamate…
Topological Sound
Xiujuan Zhang, Meng Xiao, Ying Cheng +2
Recently, we witnessed a tremendous effort to conquer the realm of acoustics as a possible playground to test with sound waves topologically protected wave propagation. Acoustics d…
Unidirectional zero sonic reflection in passive symmetric Willis media
Aurélien Merkel, Vicent Romero-García, Jean-Philippe Groby +2
In an effective medium description of acoustic metamaterials, the Willis coupling plays the same role as the bianisotropy in electromagnetism. Willis media can be described by a co…
Localized Surface Plasmons in Vibrating Graphene Nanodisks
Weihua Wang, Bo-Hong Li, Erik Stassen +2
Localized surface plasmons are confined collective oscillations of electrons in metallic nanoparticles. When driven by light, the optical response is dictated by geometrical parame…
Extraordinary absorption of sound in porous lamella-crystals
J. Christensen, V. Romero-García, R. Picó +5
We present the design of a structured material supporting complete absorption of sound with a broadband response and functional for any direction of incident radiation. The structu…