Observation of multiple rotons and multidirectional roton-like dispersion relations in acoustic metamaterials

Zhu, Zhenxiao1; Gao, Zhen1; Liu, Gui-Geng2; Ge, Yong3; Wang, Yin3; Xi, Xiang1; Yan, Bei1; Chen, Fujia4; Shum, Perry Ping1; Sun, Hong-xiang3; Yang, Yihao4

2022-12-01

10.1088/1367-2630/aca786

NEW JOURNAL OF PHYSICS   Impact Factor & Quartile

1367-2630

Roton dispersion relations were firstly predicted by Landau and have been extensively explored in correlated quantum systems at low temperatures. Recently, the roton-like dispersion relations were theoretically extended to classical acoustics, which, however, have remained elusive in reality. Here, we report the experimental observation of roton-like dispersions in acoustic metamaterials with beyond-nearest-neighbour interactions at ambient temperatures. The resulting metamaterial supports multiple coexisting modes with different wavevectors and group velocities at the same frequency and broadband backward waves, analogous to the 'return flow' termed by Feynman in the context of rotons. By increasing the order of long-range interaction, we observe multiple rotons on a single dispersion band, which have never appeared in Landau's prediction or any other condensed-matter or classical-wave studies. Moreover, we have also theoretically proposed and experimentally observed multidirectional roton-like dispersion relations in a two-dimensional nonlocal acoustic metamaterial. The realization of roton-like dispersions in metamaterials could pave the way to explore novel physics and applications on quantum-inspired phenomena in classical systems.

long-range interaction roton-like dispersion multiple rotons multidirectional roton-like dispersion nonlocal acoustic metamaterials

SCI

English

First ; Corresponding

National Natural Science Foundation of China["12104211","6101020101","12274183","12174159"] ; SUSTech Start-up Grant["Y01236148","Y01236248"] ; Key Research and Development Program of the Ministry of Science and Technology["2022YFA1404902","2022YFA1405201"] ; National Natural Science Foundation of China (NNSFC)[62175215] ; Fundamental Research Funds for the Central Universities[2021FZZX001-19] ; State Key Laboratory of Acoustics, Chinese Academy of Science[SKLA202216]

Physics

Physics, Multidisciplinary

WOS:000898975500001

IOP Publishing Ltd

PHYSICS

Web of Science

1.Southern Univ Sci & Technol, Dept Elect & Elect Engn, Shenzhen 518055, Peoples R China
2.Nanyang Technol Univ, Sch Phys & Math Sci, Div Phys & Appl Phys, 21 Nanyang Link, Singapore 637371, Singapore
3.Jiangsu Univ, Sch Phys & Elect Engn, Zhenjiang 212013, Peoples R China
4.Zhejiang Univ, Interdisciplinary Ctr Quantum Informat, ZJU Hangzhou Global Sci & Technol Innovat Ctr, State Key Lab Modern Opt Instrumentat, Hangzhou 310027, Peoples R China

Zhu, Zhenxiao,Gao, Zhen,Liu, Gui-Geng,et al. Observation of multiple rotons and multidirectional roton-like dispersion relations in acoustic metamaterials[J]. NEW JOURNAL OF PHYSICS,2022,24(12).

Zhu, Zhenxiao.,Gao, Zhen.,Liu, Gui-Geng.,Ge, Yong.,Wang, Yin.,...&Yang, Yihao.(2022).Observation of multiple rotons and multidirectional roton-like dispersion relations in acoustic metamaterials.NEW JOURNAL OF PHYSICS,24(12).

Zhu, Zhenxiao,et al."Observation of multiple rotons and multidirectional roton-like dispersion relations in acoustic metamaterials".NEW JOURNAL OF PHYSICS 24.12(2022).