Merging bound states in the continuum in an open acoustic resonator

作     者：Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas F.Sadreev Yong Li Andrey E.Miroshnichenko 

作者机构：School of Physics and Electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University School of Engineering and Technology University of New South Wales at Canberra 

出 版 物：《Science China(Physics,Mechanics & Astronomy)》 (中国科学:物理学 力学 天文学(英文版))

年 卷 期：2025年第Mechanics & Astronomy) .卷第1期

页      面：124-131页

核心收录：

学科分类：07[理学] 082403[工学-水声工程] 08[工学] 070206[理学-声学] 0824[工学-船舶与海洋工程] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China (Grant No. 12074286) Shanghai Science and Technology Committee (Grant No. 21JC1405600) supported by the Australian Research Council Discovery Project (Grant No. DP200101353) supported by Russian Science Foundation (Grant No. 22-12-00070) 

主　　题：acoustic resonances bound state in the continuum high-Q resonances 

摘      要：Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.