Selected by journal

B. Hu, Z. Zhang, H. Zhang, L. Zheng, W. Xiong, Z. Yue, X. Wang, J. Xu, Y. Cheng, X. Liu, and J. Christensen
“Non-Hermitian topological whispering gallery”
Nature 597, 655 (2021). [pdf]

X. Zhang, F. Zangeneh-Nejad, Z.-G. Chen, M.-H. Lu, and J. Christensen
“A Second Wave of Topological Phenomena in Photonics and Acoustics”
Nature 618, 687 (2023). [pdf]

S. A. Cummer, J. Christensen and A. Alu
“Controlling sound with acoustic metamaterials”
Nature Reviews Materials 1, 16001 (2016). [pdf]
Selected by the editor to be free during the APS March Meeting 2018.

K. Bertoldi, V. Vitelli, J. Christensen, and M. van Hecke
“Flexible mechanical metamaterials”
Nature Reviews Materials 2, 17066 (2017). [pdf]
Cover story [👌]

Z. Zhang, Y. Tian, Y. Wang, S. Gao, Y. Cheng, X. Liu, and J. Christensen
“Directional acoustic antennas based on valley-Hall topological insulators”
Advanced Materials 30, 1803229 (2018). [pdf]

Z. Zhang, H. Long, C. Liu, C. Shao, Y. Cheng, X. Liu, and J. Christensen
“Deep-subwavelength holey acoustic second-order topological insualators”
Advanced Materials 31, 1904682 (2019). [pdf]
Cover story [👌]

C.-W. Chen, N. Lera, R. Chaunsali, D. Torrent, J. V. Alvarez, J. Yang, P. San-Jose, and J. Christensen
“Mechanical analogue of a Majorana bound state”
Advanced Materials 31, 1904386 (2019). [pdf]

J. Liu, Z. Li, Y. Ding, A. Chen, B. Liang, J. Yang, J.-C. Cheng, and J. Christensen
“Twisting linear to orbital angular momentum in an ultrasonic motor”
Advanced Materials 34, 2201575 (2022). [pdf]
Cover story [👌]

Y. Jia, Y. Liu, B. Hu, W. Xiong, Y. Bai, Y. Cheng, D. Wu, X. Liu, and J. Christensen
“Orbital angular momentum multiplexing in space-time thermoacoustic metasurfaces”
Advanced Materials 34, 2202026 (2022). [pdf]
Cover story [👌]

J. Zheng , L. Zheng , S. Yu , S. Yang , L. Liu , X. Sun, Y.-F. Chen, M.-H. Lu, and J. Christensen
“Focusing micromechanical polaritons in topologically nontrivial hyperbolic metasurfaces”
Accepted to Advanced Materials (2024).

J. Christensen, A.I. Fernandez-Dominguez, F. de Leon-Perez, L. Martin-Moreno and F. J. Garcia-Vidal
“Collimation of sound assisted by acoustic surface waves”
Nature Physics 3, 851 (2007). [pdf]
Among the research highlights in Nature 450, 4 (2007). [pdf]

J. Zhu*, J. Christensen*, J. Jung, L. Martin-Moreno, X. Yin, L. Fok, F. J. Garcia-Vidal and Xiang Zhang
“A Holey structured metamaterial for acoustic deep subwavelength imaging”
Nature Physics 7, 52 (2011). [pdf] *These authors contributed equally.

P. Gao and J. Christensen
“Topological vortices for sound and light”
Nature Nanotechnology 16, 487 (2021). [pdf]

M. Willatzen, P. Gao, J. Christensen, and Z. L. Wang
“Acoustic gain in solids due to piezoelectricity, flexoelectricity, and electrostriction”
Advanced Functional Materials 30, 2003503 (2020). [pdf]

J. Christensen, Martin-Moreno and F. J. Garcia-Vidal,
“Theory of resonant acoustic transmission through subwavelength apertures”
Physical Review Letters 101, 014301 (2008). [pdf]

J. Christensen and F. J. Garcia de Abajo
“Anisotropic metamaterials for full control of acoustic waves”
Physical Review Letters 108, 124301 (2012). [pdf]

V.M. Garcia-Chocano, J. Christensen and J. Sánchez-Dehesa
“Negative refraction and energy funneling by hyperbolic materials: An experimental demonstration in acoustics”
Physical Review Letters 112, 144301 (2014). [pdf]

J. Christensen. M. Willatzen. V. R. Velasco and M.-H. Lu
“Parity-time synthetic phononic media”
Physical Review Letters 116, 207601 (2016). [pdf]

M. Wang, L. Ye, J. Christensen, and Z. Liu
“Valley Physics in non-Hermitian artificial Acoustic Boron Nitride”
Physical Review Letters 120, 246601 (2018). [pdf]

Z. Zhang, M. Rosendo Lopez, Y. Cheng, X. Liu, and J. Christensen
“Non-Hermitian sonic second-order topological insulator”
Physical Review Letters 122, 195501 (2019). [pdf]

P. Gao, D. Torrent, F. Cervera, P. San-Jose, J. Sanchez-Dehesa, and J. Christensen
“Majorana-like zero modes in Kekulé distorted sonic lattices”
Physical Review Letters 123, 196601 (2019). [pdf]
Cover story [👌]

M. Rosendo-Lopez, F. Peñaranda, J. Christensen, and P. San-Jose
“Flat bands in magic-angle vibrating plates”
Physical Review Letters 125, 214301 (2020). [pdf]

P. Gao, M. Willatzen, and J. Christensen
“Anomalous topological edge states in non-Hermitian piezophononic media”
Physical Review Letters 125, 206402 (2020). [pdf]

C. Liu, W. Zhao, J. Shi, X. Zhou, C. Ma, R. Peng, M. Wang, Z. H. Hang, J. Christensen, N. X. Fang, and Y. Lai
“A three-dimensional soundproof acoustic metacage”
Physical Review Letters 127, 084301 (2021). [pdf]
Editors’ suggestion.

L. Zheng and J. Christensen
“Dirac hierarchy in acoustic topological insulators”
Physical Review Letters 127, 156401 (2021). [pdf]

B. Hu, Z. Zhang, Z. Yue, D. Liao, Y. Liu, H. Zhang, Y. Cheng, X. Liu, and J. Christensen
“Anti-parity-time symmetry in a Su-Schrieffer-Heeger sonic lattice”
Physical Review Letters 131, 066601 (2023). [pdf]
Editors’ suggestion, Cover story [👌]

G. Ma, C. Fu, G. Wang, P. del Hougne, J. Christensen, Y. Lai and P. Sheng
“Polarization Bandgaps and Fluid-like Elasticity in Fully Solid Elastic Metamaterials”
Nature Communications 7, 13536 (2016). [pdf]

J. Zhang, W. Rui, C. Ma, Y. Cheng, X. Liu, and J. Christensen
“Remote Whispering Metamaterial: Non-radiative transceiving of ultra-weak sound”
Nature Communications 12, 3670 (2021). [pdf]

Z. Zhang, P. Gao, W. Liu, Z. Yue, Y. Cheng, X. Liu, and J. Christensen
“Structured sonic tube with carbon nanotube-like topological edge states”
Nature Communications 13, 5096 (2022). [pdf]

H.-X. Li, J.-J. Liu, Z.-X. Chen, K. Wu, B. Liang, J.-C. Cheng, and J. Christensen
“Superwavelength Self-Healing of Spoof Surface Sonic Airy-Talbot Waves”
Nature Communications 14, 7633 (2023). [pdf]

R. Pernas, L. Zheng, Z. Zhang, P. Gao, X. Liu, C. Ying, and Johan Christensen
“Theory of non-Hermitian topological whispering gallery”
NPJ Computational Materials 8, 241 (2022). [pdf]

L. Zheng, X. Zhang, M.-H. Lu, Y.-F. Chen, and J. Christensen
“Knitting topological bands in artificial sonic semimetals”
Materials Today Physics 16, 100299 (2021). [pdf]

X. Zhang, M. Xiao, Y. Cheng, M.-H. Lu, and J. Christensen
“Topological Sound”
Communications Physics 1, 97 (2018). [pdf]

M. Rosendo-Lopez, Z. Zhang, D. Torrent, and J. Christensen
“Multiple scattering theory of non-Hermitian sonic second-order topological insulators”
Communications Physics 2, 132 (2019). [pdf]

A. Merkel and J. Christensen
“Ultrasonic nodal chains in topological granular metamaterials”
Communications Physics 2, 154 (2019). [pdf]

J. Christensen and F. J. Garcia de Abajo
“Slow plasmonic slab waveguide as a superlens for visible light”
Physical Review B (Rapid Communication) 82, 161103 (2010). [pdf]

J. Christensen, Z. Liang, and M. Willatzen
“Metadevices for the confinement of sound and broadband double-negativity behavior”
Physical Review B (Rapid Communication) 88, 100301 (2013). [pdf]
A figure of this article has been chosen as a PRB Kaleidoscope [image].

M. Willatzen, and J. Christensen
“Acoustic gain in piezoelectric semiconductors at ɛ-near-zero response”
Physical Review B (Rapid Communication) 89, 041201 (2014). [pdf]

Z. Zhang, Y. Tian, Y. Cheng, X. Liu, and J. Christensen
“Experimental verification of acoustic pseudospin multipoles in a symmetry-broken snowflakelike topological insulator”
Physical Review B (Rapid Communication) 96, 241306 (2017). [pdf]
A figure of this article has been chosen as a PRB Kaleidoscope [image].

A.Merkel, V. Romero-Garcia, J.-P. Groby, J. Li, and J. Christensen
“Unidirectional zero sonic reflection in passive PT-symmetric Willis media”
Physical Review B (Rapid Communication) 98, 201102 (2018). [pdf]

P. Gao, Z. Zhang, and J. Christensen
“Sonic valley-Chern insulators”
Physical Review B (Rapid Communication) 101, 020301 (2020). [pdf]

Z. Zhang, B. Hu, F. Liu, Y. Cheng, X. Liu, and J. Christensen
“Pseudospin induced topological corner state at intersecting sonic lattices”
Physical Review B (Rapid Communication) 101, 220102 (2020). [pdf]