Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-30T05:45:50.746Z Has data issue: false hasContentIssue false
  • English
  • Français

Loss in acoustic metasurfaces: a blessing in disguise

Published online by Cambridge University Press:  14 November 2019

Nikhil JRK Gerard  and
Yun Jing Open the ORCID record for Yun Jing [Opens in a new window]
Nikhil JRK Gerard
Affiliation:
Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC27695, USA
Yun Jing*
Affiliation:
Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC27695, USA
*
Address all correspondence to Yun Jing at [email protected]
Get access

Abstract

From being an unfavorable consequence to finding itself as the intended imaginary part of a non-Hermitian system, loss has truly emerged as more of a friend than a foe in the context of acoustic metasurfaces. With the promising features of sub-wavelength geometries and the rapid advances in manufacturing techniques that can enable their realization, loss becomes a central topic of discussion. Further, the capability of introducing and tailoring loss allows it to serve as a new degree of freedom in passive wavefront shaping devices. In this review, the authors look back at the recent progress in the field of lossy acoustic metasurfaces. The background behind loss in deep sub-wavelength geometries and the instinctive responses to treat them and exploit them are overviewed, followed by more recent works that embrace and tailor their behavior for unconventional applications. The forthcoming years for acoustic metasurfaces thus hold several promising avenues for exploration, with loss as the protagonist.

Type
Prospective Articles
Information
MRS Communications , Volume 10 , Issue 1 , March 2020 , pp. 32 - 41
Check for updates
Copyright
Copyright © Materials Research Society 2019

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Assouar, B., Liang, B., Wu, Y., Li, Y., Cheng, J.C., and Jing, Y.: Acoustic metasurfaces. Nat. Rev. Mater. (2018). doi:10.1038/s41578-018-0061-4CrossRefGoogle Scholar
2.Li, Y. and Assouar, M.B.: Three-dimensional collimated self-accelerating beam through acoustic metascreen. Sci. Rep. (2015). doi:10.1038/srep17612Google ScholarPubMed
3.Melde, K., Mark, A.G., Qiu, T., and Fischer, P.: Holograms for acoustics. Nature (2016). doi:10.1038/nature19755CrossRefGoogle ScholarPubMed
4.Xie, Y., Shen, C., Wang, W., Li, J., Suo, D., Popa, B.I., Jing, Y., and Cummer, S.A.: Acoustic holographic rendering with two-dimensional metamaterial-based passive phased array. Sci. Rep. (2016). doi:10.1038/srep35437.Google ScholarPubMed
5.Zhu, Y., Hu, J., Fan, X., Yang, J., Liang, B., Zhu, X., and Cheng, J.: Fine manipulation of sound via lossy metamaterials with independent and arbitrary reflection amplitude and phase. Nat. Commun. (2018). doi:10.1038/s41467-018-04103-0Google ScholarPubMed
6.Cheng, Y., Zhou, C., Yuan, B.G., Wu, D.J., Wei, Q., and Liu, X.J.: Ultra-sparse metasurface for high reflection of low-frequency sound based on artificial Mie resonances. Nat. Mater. (2015). doi:10.1038/nmat4393CrossRefGoogle ScholarPubMed
7.Shen, C., Díaz-Rubio, A., Li, J., and Cummer, S.A.: A surface impedance-based three-channel acoustic metasurface retroreflector. Appl. Phys. Lett. (2018). doi:10.1063/1.5025481CrossRefGoogle Scholar
8.Song, G.Y., Cheng, Q., Cui, T.J., and Jing, Y.: Acoustic planar surface retroreflector. Phys. Rev. Mater. (2018). doi:10.1103/PhysRevMaterials.2.065201CrossRefGoogle Scholar
9.Shen, C., Xie, Y., Li, J., Cummer, S.A., and Jing, Y.: Asymmetric acoustic transmission through near-zero-index and gradient-index metasurfaces. Appl. Phys. Lett. (2016). doi:10.1063/1.4953264CrossRefGoogle Scholar
10.Li, Y., Shen, C., Xie, Y., Li, J., Wang, W., Cummer, S.A., and Jing, Y.: Tunable asymmetric transmission via lossy acoustic metasurfaces. Phys. Rev. Lett. (2017). doi:10.1103/PhysRevLett.119.035501Google ScholarPubMed
11.Zhu, Y., Fan, X., Liang, B., Cheng, J., and Jing, Y.: Ultrathin acoustic metasurface-based schroeder diffuser. Phys. Rev. X (2017). doi:10.1103/PhysRevX.7.021034Google Scholar
12.Jiménez, N., Cox, T.J., Romero-García, V., and Groby, J.P.: Metadiffusers: deep-subwavelength sound diffusers. Sci. Rep. (2017). doi:10.1038/s41598-017-05710-5CrossRefGoogle ScholarPubMed
13.Mei, J., Ma, G., Yang, M., Yang, Z., Wen, W., and Sheng, P.: Dark acoustic metamaterials as super absorbers for low-frequency sound. Nat. Commun. (2012). doi:10.1038/ncomms1758CrossRefGoogle ScholarPubMed
14.Li, Y. and Assouar, B.M.: Acoustic metasurface-based perfect absorber with deep subwavelength thickness. Appl. Phys. Lett. (2016). doi:10.1063/1.4941338Google Scholar
15.Yang, M. and Sheng, P.: Sound absorption structures: from porous media to acoustic metamaterials. Annu. Rev. Mater. Res. (2017). doi:10.1146/annurev-matsci-070616-124032CrossRefGoogle Scholar
16.Yang, M., Chen, S., Fu, C., and Sheng, P.: Optimal sound-absorbing structures. Mater. Horizons (2017). doi:10.1039/c7mh00129kCrossRefGoogle Scholar
17.Kirchhoff, G.: Ueber den Einfluss der Wärmeleitung in einem Gase auf die Schallbewegung. Ann. Phys. (1868). doi:10.1002/andp.18682100602CrossRefGoogle Scholar
18.Strutt, J.W. and Rayleigh, B.: The theory of sound - volume I. Nature (1877). doi:10.1038/058121a0Google Scholar
19.Rayleigh, J.W.S.: The Theory of Sound, Vol. II. (1896).Google Scholar
20.Cox, T.J.. Acoustic Absorbers and Diffusers. (Spoon Press, 2002). doi:10.1201/9781482288254CrossRefGoogle Scholar
21.Theocharis, G., Richoux, O., García, V.R., Merkel, A., and Tournat, V.: Limits of slow sound propagation and transparency in lossy, locally resonant periodic structures. N. J. Phys (2014). doi:10.1088/1367-2630/16/9/093017.CrossRefGoogle Scholar
22.Molerón, M., Serra-Garcia, M., and Daraio, C.: Visco-thermal effects in acoustic metamaterials: from total transmission to total reflection and high absorption. N. J. Phys (2016). doi:10.1088/1367-2630/18/3/033003.CrossRefGoogle Scholar
23.Ward, G.P., Lovelock, R.K., Murray, A.R.J., Hibbins, A.P., Sambles, J.R., and Smith, J.D.: Boundary-layer effects on acoustic transmission through narrow slit cavities. Phys. Rev. Lett. (2015). doi:10.1103/PhysRevLett.115.044302CrossRefGoogle ScholarPubMed
24.Henríquez, V.C., García-Chocano, V.M., and Sánchez-Dehesa, J.: Viscothermal losses in double-negative acoustic metamaterials. Phys. Rev. Appl. (2017). doi:10.1103/PhysRevApplied.8.014029CrossRefGoogle Scholar
25.Liang, Z. and Li, J.: Extreme acoustic metamaterial by coiling up space. Phys. Rev. Lett. (2012). doi:10.1103/PhysRevLett.108.114301CrossRefGoogle ScholarPubMed
26.Li, Y., Liang, B., Tao, X., Zhu, X.F., Zou, X.Y., and Cheng, J.C.: Acoustic focusing by coiling up space. Appl. Phys. Lett. (2012). doi:10.1063/1.4769984Google Scholar
27.Xie, Y., Konneker, A., Popa, B.I., and Cummer, S.A.: Tapered labyrinthine acoustic metamaterials for broadband impedance matching. Appl. Phys. Lett. (2013). doi:10.1063/1.4831770CrossRefGoogle Scholar
28.Liang, Z., Feng, T., Lok, S., Liu, F., Ng, K.B., Chan, C.H., Wang, J., Han, S., Lee, S., and Li, J.: Space-coiling metamaterials with double negativity and conical dispersion. Sci. Rep. (2013). doi:10.1038/srep01614CrossRefGoogle ScholarPubMed
29.Li, Y., Jiang, X., Liang, B., Cheng, J.C., and Zhang, L.: Metascreen-based acoustic passive phased array. Phys. Rev. Appl. (2015). doi:10.1103/PhysRevApplied.4.024003Google Scholar
30.Li, Y., Qi, S., and Assouar, M.B.: Theory of metascreen-based acoustic passive phased array. New J. Phys. 18, 043024 (2016).CrossRefGoogle Scholar
31.Xie, Y., Wang, W., Chen, H., Konneker, A., Popa, B.I., and Cummer, S.A.: Wavefront modulation and subwavelength diffractive acoustics with an acoustic metasurface. Nat. Commun. (2014). doi:10.1038/ncomms6553CrossRefGoogle ScholarPubMed
32.Liu, B., Zhao, W., and Jiang, Y.: Full-angle negative reflection realized by a gradient acoustic metasurface. AIP Adv. (2016). doi:10.1063/1.4967430CrossRefGoogle Scholar
33.Wang, W., Xie, Y., Popa, B.I., and Cummer, S.A.: Subwavelength diffractive acoustics and wavefront manipulation with a reflective acoustic metasurface. J. Appl. Phys. (2016). doi:10.1063/1.4967738CrossRefGoogle Scholar
34.Li, Y., Liang, B., Gu, Z.M., Zou, X.Y., and Cheng, J.C.: Reflected wavefront manipulation based on ultrathin planar acoustic metasurfaces. Sci. Rep. (2013). doi:10.1038/srep02546Google ScholarPubMed
35.Jiang, X., Li, Y., and Zhang, L.: Thermoviscous effects on sound transmission through a metasurface of hybrid resonances. J. Acoust. Soc. Am. (2017). doi:10.1121/1.4979682CrossRefGoogle ScholarPubMed
36.Gerard, N.J., Cui, H., Shen, C., Xie, Y., Zheng, X., Cummer, S.A., and Jing, Y.: Fabrication and experimental demonstration of a hybrid resonant acoustic gradient index metasurface at 40 kHz. Appl. Phys. Lett. (2019). doi:10.1063/1.5095963CrossRefGoogle Scholar
37.Gerard, N.J., Li, Y., and Jing, Y.: Investigation of acoustic metasurfaces with constituent material properties considered. J. Appl. Phys. (2018). doi:10.1063/1.5007863CrossRefGoogle Scholar
38.Zhu, Y. and Assouar, B.: Systematic design of multiplexed-acoustic-metasurface hologram with simultaneous amplitude and phase modulations. Phys. Rev. Mater. (2019). doi:10.1103/PhysRevMaterials.3.045201CrossRefGoogle Scholar
39.Arenas, J.P. and Crocker, M.J.: Recent trends in porous sound-absorbing materials. Sound Vib. (2010).Google Scholar
40.Allard, J.F.. Propagation of Sound in Porous Media. 1993. doi:10.1007/978-94-011-1866-8CrossRefGoogle Scholar
41.Kang, J. and Fuchs, H.V.: Predicting the absorption of open weave textiles and micro-perforated membranes backed by an air space. J. Sound Vib. (1999). doi:10.1006/jsvi.1998.1977CrossRefGoogle Scholar
42.Maa, D.Y.: Theory and design of microperforated panel sound-absorbing constructions. Sci. Sin. (1975).Google Scholar
43.Maa, D.-Y.: Potential of microperforated panel absorber. J. Acoust. Soc. Am. (1998). doi:10.1121/1.423870CrossRefGoogle Scholar
44.Huang, T.-Y., Shen, C., and Jing, Y.: Membrane- and plate-type acoustic metamaterials. J. Acoust. Soc. Am. (2016). doi:10.1121/1.4950751Google ScholarPubMed
45.Yang, M., Meng, C., Fu, C., Li, Y., Yang, Z., and Sheng, P.: Subwavelength total acoustic absorption with degenerate resonators. Appl. Phys. Lett. (2015). doi:10.1063/1.4930944Google Scholar
46.Ma, G., Yang, M., Xiao, S., Yang, Z., and Sheng, P.: Acoustic metasurface with hybrid resonances. Nat. Mater. (2014). doi:10.1038/nmat3994CrossRefGoogle ScholarPubMed
47.Huang, S., Fang, X., Wang, X., Assouar, B., Cheng, Q., and Li, Y.: Acoustic perfect absorbers via spiral metasurfaces with embedded apertures. Appl. Phys. Lett. (2018). doi:10.1063/1.5063289CrossRefGoogle Scholar
48.Huang, S., Fang, X., Wang, X., Assouar, B., Cheng, Q., and Li, Y.: Acoustic perfect absorbers via Helmholtz resonators with embedded apertures. J. Acoust. Soc. Am. (2019). doi:10.1121/1.5087128CrossRefGoogle ScholarPubMed
49.Long, H., Cheng, Y., Tao, J., and Liu, X.: Perfect absorption of low-frequency sound waves by critically coupled subwavelength resonant system. Appl. Phys. Lett. (2017). doi:10.1063/1.4973925Google Scholar
50.Ryoo, H. and Jeon, W.: Perfect sound absorption of ultra-thin metasurface based on hybrid resonance and space-coiling. Appl. Phys. Lett. (2018). doi:10.1063/1.5049696CrossRefGoogle Scholar
51.Peng, X., Ji, J., and Jing, Y.: Composite honeycomb metasurface panel for broadband sound absorption. J. Acoust. Soc. Am. (2018). doi:10.1121/1.5055847CrossRefGoogle ScholarPubMed
52.Long, H., Gao, S., Cheng, Y., and Liu, X.: Multiband quasi-perfect low-frequency sound absorber based on double-channel Mie resonator. Appl. Phys. Lett. (2018). doi:10.1063/1.5013225CrossRefGoogle Scholar
53.Li, Y., Jiang, X., Li, R.Q., Liang, B., Zou, X.Y., Yin, L.L., and Cheng, J.C.: Experimental realization of full control of reflected waves with subwavelength acoustic metasurfaces. Phys. Rev. Appl. (2014). doi:10.1103/PhysRevApplied.2.064002CrossRefGoogle Scholar
54.Memoli, G., Caleap, M., Asakawa, M., Sahoo, D.R., Drinkwater, B.W., and Subramanian, S.: Metamaterial bricks and quantization of meta-surfaces. Nat. Commun. (2017). doi:10.1038/ncomms14608CrossRefGoogle ScholarPubMed
55.Tang, H., Chen, Z., Tang, N., Li, S., Shen, Y., Peng, Y., Zhu, X., and Zang, J.: Hollow-out patterning ultrathin acoustic metasurfaces for multifunctionalities using soft fiber/rigid bead networks. Adv. Funct. Mater. (2018). doi.org/10.1002/adfm.201801127Google Scholar
56.Zhao, J., Ye, H., Huang, K., Chen, Z.N., Li, B., and Qiu, C.W.: Manipulation of acoustic focusing with an active and configurable planar metasurface transducer. Sci. Rep. (2014). doi:10.1038/srep06257Google ScholarPubMed
57.Shen, Y., Zhu, X., Cai, F., Ma, T., Li, F., Xia, X., Li, Y., Wang, C., and Zheng, H.: Active acoustic metasurface: complete elimination of grating lobes for high-quality ultrasound focusing and controllable steering. Phys. Rev. Appl. (2019). doi:10.1103/PhysRevApplied.11.034009CrossRefGoogle Scholar
58.Tian, Z., Shen, C., Li, J., Reit, E., Gu, Y., Fu, H., Cummer, S.A., and Huang, T.J.: Programmable acoustic metasurfaces. Adv. Funct. Mater. (2019). doi:10.1002/adfm.201808489CrossRefGoogle ScholarPubMed
59.Chen, S., Fan, Y., Fu, Q., Wu, H., Jin, W., Zheng, J., and Zhang, F.: A review of tunable acoustic metamaterials. Appl. Sci. (2018). doi:10.3390/app8091480Google Scholar
60.Xu, Y., Fu, Y., and Chen, H.: Planar gradient metamaterials. Nat. Rev. Mater. (2016). doi:10.1038/natrevmats.2016.67CrossRefGoogle Scholar
61.Yu, N., Genevet, P., Kats, M.A., Aieta, F., Tetienne, J.P., Capasso, F., and Gaburro, Z.: Light propagation with phase discontinuities: generalized laws of reflection and refraction. Science (2011). doi:10.1126/science.1210713CrossRefGoogle ScholarPubMed
62.Mei, J. and Wu, Y.: Controllable transmission and total reflection through an impedance-matched acoustic metasurface. N. J. Phys (2014). doi:10.1088/1367-2630/16/12/123007.CrossRefGoogle Scholar
63.Shen, C. and Cummer, S.A.: Harnessing multiple internal reflections to design highly absorptive acoustic metasurfaces. Phys. Rev. Appl. (2018). doi:10.1103/PhysRevApplied.9.054009CrossRefGoogle Scholar
64.Fu, Y., Shen, C., Cao, Y., Gao, L., Chen, H., Chan, C.T., Cummer, S.A., and Xu, Y.: Reversal of transmission and reflection based on acoustic metagratings with integer parity design. Nat. Commun. (2019). doi:10.1038/s41467-019-10377-9CrossRefGoogle ScholarPubMed
65.Ju, F., Tian, Y., Cheng, Y., and Liu, X.: Asymmetric acoustic transmission with a lossy gradient-index metasurface. Appl. Phys. Lett. (2018). doi:10.1063/1.5032263CrossRefGoogle Scholar
66.Shen, C., Xie, Y., Li, J., Cummer, S.A., and Jing, Y.: Acoustic metacages for sound shielding with steady air flow. J. Appl. Phys. (2018). doi:10.1063/1.5009441Google Scholar
67.Fu, Y., Cao, Y., and Xu, Y.: Multifunctional reflection in acoustic metagratings with simplified design. Appl. Phys. Lett. (2019). doi:10.1063/1.5083081CrossRefGoogle Scholar
68.Zhu, X.F. and Lau, S.K.: Reflected wave manipulation via acoustic metamaterials with decoupled amplitude and phase. Appl. Phys. A Mater. Sci. Process. (2019). doi:10.1007/s00339-019-2687-5CrossRefGoogle Scholar
69.Wang, X., Fang, X., Mao, D., Jing, Y., and Li, Y.: Extremely asymmetrical acoustic metasurface mirror at the exceptional point. Phys. Rev. Lett. (2019), ( in press ).CrossRefGoogle ScholarPubMed
70.Zhu, Y. and Assouar, B.: Multifunctional acoustic metasurface based on an array of Helmholtz resonators. Phys. Rev. B (2019). doi:10.1103/PhysRevB.99.174109Google Scholar
71.Bender, C.M. and Boettcher, S.: Real spectra in non-Hermitian hamiltonians having PT symmetry. Phys. Rev. Lett. (1998). doi:10.1103/PhysRevLett.80.5243CrossRefGoogle Scholar
72.Bender, C.M.: Making sense of non-Hermitian hamiltonians. Rep. Prog. Phys. (2007). doi:10.1088/0034-4885/70/6/R03CrossRefGoogle Scholar
73.Rüter, C.E., Makris, K.G., El-Ganainy, R., Christodoulides, D.N., Segev, M., and Kip, D.: Observation of parity-time symmetry in optics. Nat. Phys. (2010). doi:10.1038/nphys1515CrossRefGoogle Scholar
74.Peng, B., Özdemir, S.K., Lei, F., Monifi, F., Gianfreda, M., Long, G.L., Fan, S., Nori, F., Bender, C.M., and Yang, L.: Parity-time-symmetric whispering-gallery microcavities. Nat. Phys. (2014). doi:10.1038/nphys2927CrossRefGoogle Scholar
75.Feng, L., Xu, Y.L., Fegadolli, W.S., Lu, M.H., Oliveira, J.E.B., Almeida, V.R., Chen, Y.F., and Scherer, A.: Experimental demonstration of a unidirectional reflectionless parity-time metamaterial at optical frequencies. Nat. Mater. (2013). doi:10.1038/nmat3495CrossRefGoogle ScholarPubMed
76.Sun, Y., Tan, W., Li, H.Q., Li, J., and Chen, H.: Experimental demonstration of a coherent perfect absorber with pt phase transition. Phys. Rev. Lett. (2014). doi:10.1103/PhysRevLett.112.143903CrossRefGoogle ScholarPubMed
77.Chong, Y.D., Ge, L., and Stone, A.D.: PT-symmetry breaking and laser-absorber modes in optical scattering systems. Phys. Rev. Lett. (2011). doi:10.1103/PhysRevLett.106.093902CrossRefGoogle ScholarPubMed
78.Feng, L., Wong, Z.J., Ma, R.M., Wang, Y., and Zhang, X.: Single-mode laser by parity-time symmetry breaking. Science (2014). doi:10.1126/science.1258479CrossRefGoogle ScholarPubMed
79.Hodaei, H., Miri, M.A., Heinrich, M., Christodoulides, D.N., and Khajavikhan, M.: Parity-time-symmetric microring lasers. Science (2014). doi:10.1126/science.1258480CrossRefGoogle ScholarPubMed
80.Peng, B., Özdemir, S.K., Rotter, S., Yilmaz, H., Liertzer, M., Monifi, F., Bender, C.M., Nori, F., and Yang, L.: Loss-induced suppression and revival of lasing. Science (2014). doi:10.1126/science.1258004CrossRefGoogle ScholarPubMed
81.Hodaei, H., Hassan, A.U., Wittek, S., Gracia, H.G., Ganainy, R.E., Christodoulides, D.N., and Khajavikhan, M.: Enhanced sensitivity at higher-order exceptional points. Nature (2017). doi:10.1038/nature23280Google ScholarPubMed
82.Chen, W., Özdemir, ŞK, Zhao, G., Wiersig, J., and Yang, L.: Exceptional points enhance sensing in an optical microcavity. Nature (2017). doi:10.1038/nature23281CrossRefGoogle Scholar
83.Fleury, R., Sounas, D., and Alù, A.: An invisible acoustic sensor based on parity-time symmetry. Nat. Commun. (2015). doi:10.1038/ncomms6905CrossRefGoogle ScholarPubMed
84.Zhu, X., Ramezani, H., Shi, C., Zhu, J., and Zhang, X.: PT-symmetric acoustics. Phys. Rev. X (2014). doi:10.1103/PhysRevX.4.031042.Google Scholar
85.Li, H.-X., Rosendo-Lopez, M., Zhu, Y.-F., Fan, X.D., Torrent, D., Liang, B., Cheng, J.C., and Christensen, J.: Ultrathin acoustic parity-time symmetric metasurface cloak. Research (2019). doi: 10.34133/2019/8345683CrossRefGoogle ScholarPubMed
86.Shi, C., Dubois, M., Chen, Y., Cheng, L., Rameszani, H., Wang, Y., and Zhang, X.: Accessing the exceptional points of parity-time symmetric acoustics. Nat. Commun. (2016). doi:10.1038/ncomms11110Google ScholarPubMed
87.Shen, C., Li, J., Peng, X., and Cummer, S.A.: Synthetic exceptional points and unidirectional zero reflection in non-Hermitian acoustic systems. Phys. Rev. Mater. (2018). doi:10.1103/PhysRevMaterials.2.125203CrossRefGoogle Scholar
88.Zhu, W., Fang, X., Li, D., Sun, Y., Li, Y., Jing, Y., and Chen, H.: Simultaneous observation of a topological edge state and exceptional point in an open and non-Hermitian acoustic system. Phys. Rev. Lett. (2018). doi:10.1103/PhysRevLett.121.124501CrossRefGoogle Scholar
89.Ding, K., Ma, G., Xiao, M., Zhang, Z.Q., and Chan, C.T.: Emergence, coalescence, and topological properties of multiple exceptional points and their experimental realization. Phys. Rev. X (2016). doi:10.1103/PhysRevX.6.021007Google Scholar
90.Ding, K., Ma, G., Zhang, Z.Q., and Chan, C.T.: Experimental demonstration of an anisotropic exceptional point. Phys. Rev. Lett. (2018). doi:10.1103/PhysRevLett.121.085702CrossRefGoogle ScholarPubMed
91.Sakhdari, M., Farhat, M., and Chen, P.Y.: PT-symmetric metasurfaces: wave manipulation and sensing using singular points. N. J. Phys (2017). doi:10.1088/1367-2630/aa6bb9.CrossRefGoogle Scholar
92.Monticone, F., Valagiannopoulos, C.A., and Alù, A.: Parity-time symmetric nonlocal metasurfaces: all-angle negative refraction and volumetric imaging. Phys. Rev. X (2016). doi:10.1103/PhysRevX.6.041018.Google Scholar
93.Ra'di, Y., Sounas, D.L., Alù, A., and Tretyakov, S.A.: Parity-time-symmetric teleportation. Phys. Rev. B (2016). doi:10.1103/PhysRevB.93.235427CrossRefGoogle Scholar
94.Kang, M., Chen, J., and Chong, Y.D.: Chiral exceptional points in metasurfaces. Phys. Rev. A (2016). doi:10.1103/PhysRevA.94.033834CrossRefGoogle Scholar
95.Jin, Y., Kumar, R., Poncelet, O., Mondain-Monval, O., and Brunet, T.: Flat acoustics with soft gradient-index metasurfaces. Nat. Commun. (2019). doi:10.1038/s41467-018-07990-5Google ScholarPubMed
96.Chen, J., Rao, J., Lisevych, D., and Fan, Z.: Broadband ultrasonic focusing in water with an ultra-compact metasurface lens. Appl. Phys. Lett. (2019). doi:10.1063/1.5090956Google Scholar
97.Cotterill, P.A., Nigro, D., Abrahams, I.D., Garcia-Neefjes, E., and Parnell, W.J.: Thermo-viscous damping of acoustic waves in narrow channels: a comparison of effects in air and water. J. Acoust. Soc. Am. (2018). doi:10.1121/1.5078528CrossRefGoogle ScholarPubMed
98.Díaz-Rubio, A. and Tretyakov, S.A.: Acoustic metasurfaces for scattering-free anomalous reflection and refraction. Phys. Rev. B (2017). doi:10.1103/PhysRevB.96.125409CrossRefGoogle Scholar
99.Li, J., Shen, C., Díaz-Rubio, A., Tretyakov, S.A., and Cummer, S.A.: Systematic design and experimental demonstration of bianisotropic metasurfaces for scattering-free manipulation of acoustic wavefronts. Nat. Commun. (2018). doi:10.1038/s41467-018-03778-9Google ScholarPubMed
100.Craig, S.R., Su, X., Norris, A., and Shi, C.: Experimental realization of acoustic bianisotropic gratings. Phys. Rev. Appl. (2019). doi:10.1103/PhysRevApplied.11.061002.CrossRefGoogle Scholar
101.Wang, X., Díaz-Rubio, A., Asadchy, V.S., Ptitcyn, G., Generalov, A.A., Laurinaho, J.A., and Tretyakov, S.A.: Extreme asymmetry in metasurfaces via evanescent fields engineering: angular-asymmetric absorption. Phys. Rev. Lett. (2018). doi:10.1103/PhysRevLett.121.256802CrossRefGoogle ScholarPubMed
102.Ra'Di, Y., Sounas, D.L., and Alù, A.: Metagratings: beyond the limits of graded metasurfaces for wave front control. Phys. Rev. Lett. (2017). doi:10.1103/PhysRevLett.119.067404CrossRefGoogle ScholarPubMed
103.Quan, L., Ra'Di, Y., Sounas, D.L., and Alù, A.: Maximum willis coupling in acoustic scatterers. Phys. Rev. Lett. (2018). doi:10.1103/PhysRevLett.120.254301CrossRefGoogle ScholarPubMed
104.Quan, L. and Alù, A.: Passive acoustic metasurface with unitary reflection based on nonlocality. Phys. Rev. Appl. (2019). doi:10.1103/PhysRevApplied.11.054077CrossRefGoogle Scholar
105.Cox, T.J.: Fast time domain modeling of surface scattering from reflectors and diffusers. J. Acoust. Soc. Am. (2015). doi:10.1121/1.4921675CrossRefGoogle ScholarPubMed