Experimental realization of sonic demultiplexing devices based on inverse designed scattering acoustic elements

We present experiments demonstrating sonic demultiplex devices able to separate spatially several wavelengths. The devices are based on clusters of circular scatterers whose position and size are determined by using an inverse design approach. Two prototypes are built and characterized, a first that spatially separates two wavelengths (i.e., 20.0 and 22.7 cm) and a second that separates three wavelengths: 20.0, 21.3, and 22.7 cm. Both prototypes are typical examples of acoustic scattering elements, a name here introduced to define inverse designed devices that are characterized by their great adaptability in controlling the scattering image, including both the reflected and transmitted waves. (c) 2006 American Institute of Physics.