Achieving electric field focusing using annular metal-dielectric multilayers.

We present studies on an electric field focuser comprised of annular epsilon-near-zero metamaterials (ENZMs) and inner free space. According to effective medium theory, annular ENZMs can be realized via annular metal-dielectric multilayers. In practice, we choose silver and air to design the focuser. Our numerical simulations demonstrate that the electric field can be focused on a fixed point, regardless of the number and location of electromagnetic sources in annular multilayers, which might be helpful for laser ignition.