Figure 1: (a) versus curve given by (3) for polymer-based and silicon-based metamaterials. (b) Beam propagation in a polymer metamaterial for a Gaussian beam with a width . The metamaterial region starts at 5 m from the bottom of the figure (the interface is indicated by a dashed line) and extends upwards. Inset: 2D Fourier transform of the spatial field in the photonic crystal. The wavevector and are indicated by a black arrow and a green dash arrow. The wavevector of various diffraction orders (on a square lattice in the reciprocal space) are marked by crosses. (c) Same as in (b) except m.