Light localization and nonlinear beam transmission in specular amorphous photonic lattices.

We demonstrate specular photonic "lattices" with random index variations at disordered positions of lattice sites. These amorphous lattice structures, optically induced in a bulk nonlinear crystal, remain invariant during propagation since they are constructed from random components residing on a fixed ring in momentum space. We observe linear spatial localization of a light beam when probing through different "defect" points in such specular lattices, as well as the nonlinear destruction of localized modes.

Toroidal dipole response in a multifold double-ring metamaterial.

The toroidal response is numerically investigated in a multifold double-ring metamaterials at the antibonding magnetic-dipole mode (i.e., antiparallel magnetic dipoles in one double-ring fold).

Transparency window for the absorptive dipole resonance in a symmetry-reduced grating structure.

We demonstrate that a transparency window can be obtained within the absorptive dipole resonant regime, by slightly reducing the symmetric arrangement of a dipole-like bar grating covered by a waveguiding layer. The physical understanding is that, under the condition of reducing the grating symmetry, the lossy dipole plasmon resonance can be completely transferred into the waveguide mode in a way of destructive interference. In accompany with the tunable transparency window modulated by the symmetry-reduced displacement, an ultra high group index (slowing down the light) as well as a vortex distribution of the electromagnetic field is found.