Damped acoustic systems have a limited quality factor due to intrinsic loss.By introducing gain elements,a method to enhance the quality factor of damped systems is proposed based on the concept of bound states in the...Damped acoustic systems have a limited quality factor due to intrinsic loss.By introducing gain elements,a method to enhance the quality factor of damped systems is proposed based on the concept of bound states in the continuum(BICs).The acoustic model under study is a two-port waveguide system installed with two side Helmholtz resonators connected by a coupling tube.Based on the temporal coupled-mode theory,a Hamiltonian matrix with both intrinsic and radiation losses is used to characterize the resonance behavior of the coupled resonators.To achieve a high quality factor,acoustic gain is introduced to compensate the intrinsic loss,leading the Hamiltonian parameters toward a quasi-BIC condition.Numerical simulation demonstrates a gain-assisted and quasi-BIC-supported extremely high quality factor in damped acoustic systems.The concept is further utilized to design a sensor model for particle size detection.The enhanced sensing performance due to high quality factors is numerically demonstrated.The findings suggest potential applications in acoustic sensing and detection devices.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12225203,11622215,and 11872111)the 111 Project(Grant No.B16003).
文摘Damped acoustic systems have a limited quality factor due to intrinsic loss.By introducing gain elements,a method to enhance the quality factor of damped systems is proposed based on the concept of bound states in the continuum(BICs).The acoustic model under study is a two-port waveguide system installed with two side Helmholtz resonators connected by a coupling tube.Based on the temporal coupled-mode theory,a Hamiltonian matrix with both intrinsic and radiation losses is used to characterize the resonance behavior of the coupled resonators.To achieve a high quality factor,acoustic gain is introduced to compensate the intrinsic loss,leading the Hamiltonian parameters toward a quasi-BIC condition.Numerical simulation demonstrates a gain-assisted and quasi-BIC-supported extremely high quality factor in damped acoustic systems.The concept is further utilized to design a sensor model for particle size detection.The enhanced sensing performance due to high quality factors is numerically demonstrated.The findings suggest potential applications in acoustic sensing and detection devices.
