Design of acoustic devices with isotropic material via conformal transformation

The known realization of transformation acoustic devices requires exotic material parameters and has been hampered by limited available materials. By merging the conformal mapping and the embedded coordinate transformation method, we demonstrate that transformation-based acoustic devices can be made from isotropic materials, which greatly facilitates their implementation. The acoustic directional antenna based on such approach is presented and validated by full-wave simulations using the finite element method. (C) 2010 American Institute of Physics. [doi:10.1063/1.3467852]