Quasi-isotropic underwater acoustic carpet cloak based on latticed pentamode metafluid

We present a practical design of an underwater acoustic carpet cloak with 2-dimensional version of the pentamode lattice. The quasi-conformal transformation, which is achieved by inverse Laplace's equations with Neumann and Dirichlet boundaries, is used to obtain the required parameters of the impedance matching carpet cloak. The theoretical carpet cloak is pre-divided into 300 cells and then filled with the corresponding pentamode material unit cells to achieve the latticed pentamode carpet cloak. The simulation results indicate that the proposed carpet cloak has a good and broadband cloaking effect. Moreover, the technique in this work can also be used to design arbitrary shaped devices.