metamaterial tagged posts

Topological transitions of a deformed kagome lattice by uniform soft twisting. Two types of triangles (red and blue) are connected by free hinges at their corners, forming a deformed kagome lattice with primitive vectors a1, a2. The angle θ between the triangles defines the twisting coordinate. The blue curve shows (defined in equation (1)) as a function of θ. The 3 white dots on the θ axis represent three critical angles (, and ) where sides of the triangles form straight lines (yellow stripes on the lattices) and topological polarization RT (shown as black arrows above the axes) changes.

This is an infrared image of metadevice composed of vanadium dioxide with gold patterned mesh. (Top) Device without any electric current showing the PSU cut from the pattern and reflective. (Middle) Device with 2.03 amps

(a) Schematic of the multimaterial projection microstereolithography system. [(b) and (e)] Computer-aided designs and fabricated samples in [(c) and (f)] three-dimensional and [(d) and (g)] two-dimensional views of the fabricated unit cell and 2 by 2 lattice, respectively.

Multilayer fishnet metamaterial. (a) Sketch of the structure. Thicknesses of MgF2 and Au layers are 45 and 30 nm, respectively. Thickness of Si3N4 membrane is 50 nm. Lattice period is 750 × 750 nm. Size of holes is 260 × 530 nm. (b) Experimentally measured transmission spectrum of the fishnet metamaterial. Inset shows a scanning electron microscopy image of the fabricated structure. (c) Effective refractive index of the fishnet metamaterial extracted for the normal incidence. The marked lines in b and c represent the wavelengths in the regions of elliptic dispersion (red), crossover optical topological transition (green) and hyperbolic dispersion (blue).