Visible-wavelength super-refraction in photonic crystal superprisms

We demonstrate the fabrication of superprism devices in photonic crystal waveguides with excellent transmission through 600 rows of 160nm diameter holes. Broadband spectral and angular measurements allow mapping of the chromatic refractivity. This shows the ability of such devices to super-refract by more than 1°∕nm close to the principal band gaps, 10× more than equivalent gratings, and 100× more than equivalent prisms. Simple theories based on plane-wave models give excellent agreement with these results.