Tunable acoustic radiation pattern assisted by effective impedance boundary
Feng Qian1, 2, Li Quan1, 3, Li-Wei Wang1, Xiao-Zhou Liu1, †, 
, Xiu-Fen Gong1
, Xiu-Fen Gong1 Schematic diagram of subwavelength slit surrounded by two metal plates decorated with Helmholtz resonators (HRs).
