Full text loading...
(Color online) (a) Schematic experiment setup. (b) Images of green opal film before (left) and after (right) applying electric field, E = 20 V/m (cover slip removed for better imaging). (c) Schematic change of effective refractive index distribution through the opal film before and after applying electric field. Filled and dashed circles indicate positions of the spheres before and after applying electric field.
(Color online) Transmission spectra of (a) infrared and (c) green opals with increasing field. (b,d) Extracted wavelengths of spectral dips (filled points) and dip amplitudes (open points) with increasing field. Solid lines show calculated dip positions, and dashed lines show predicted dip amplitudes.
(Color online) Cycling at 0.5 Hz of the field-induced switching of the photonic bandgap position between E = 0 and 12 V/m. (a) and (c) Normalized transmission spectra (colour scale) of (a) infrared and (c) green opals. (b) and (d) Extracted modulation (off = open symbols, on = filled) in spectral position (circles) and normalized transmission (triangles) at 740 nm (infrared opal) and 540 nm (green opal).
Article metrics loading...