Broadband ultra-long acoustic jet based on double-foci Luneburg lens

In this paper, a gradient index acoustic metamaterial is proposed based on the concept of the optical modified generalized Luneburg lens (MGLL). With the MGLL, double-foci and high energy density between the two foci can be achieved, which enables the realization of an ultra-long acoustic jet between the two foci. This capability of the MGLL is theoretically and numerically demonstrated with an acoustic metamaterial lens. Numerical simulation results show that based on this design, ultra-long acoustic jets with a jet length of up to 30 2 can be achieved, covering both the near field and far field. (C) 2021 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

Automated summary

In this paper, a gradient index acoustic metamaterial is proposed based on the concept of the optical modified generalized Luneburg lens (MGLL), achieving double-foci and high energy density acoustic jet between the foci. Numerical simulation results demonstrate ultra-long acoustic jets with a length of up to 30 2 can be realized with this design.