Abstract
We present a type of sonic crystal composed with an array of two-dimensional Helmholtz resonators, which in the long-wave regime have both a high relative acoustic refractive index n and at the same time, a small acoustic impedance Z mismatch with air for airborne sound. We analyze the n and Z of such sonic crystals by finite-difference time-domain simulations, and by mapping our results to a corresponding electromagnetic (EM) model, and we find that our Helmholtz resonant sonic crystal has a bigger effective magnetic permeability mu than the conventional rigid-cylinder sonic crystal in its EM counterpart. As a result, a thin convergent lens with very good focusing effect is demonstrated based on our crystal.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
