Supercontinuum based sources and measurement techniques are developed, enabling optical ultra-broadband studies of nano-scale photonic crystal devices and integrated photonic circuits over 1.2 - 2.0 micron wavelength range. Experiments involving 1-D periodic photonic crystal microcavity waveguides and 3-D periodic photonic crystals with embedded point defects are described. Experimental findings are compared with rigorous electromagnetic simulations.
We present two potentially interesting new venues in all-optical signal processing. First, we demonstrate experimentally that collisions between vector (Manakov-like) solitons involve energy exchange; this feature could be explored for all-optical signal processing. Second, our detailed theoretical studies show how inserting materials that support electro-magnetically induced transparency into microcavities enables design of microcavities with extraordinarily long lifetimes, and enables all-optical signal processing at single photon power levels.
Using detailed numerical simulations, and analytical theory, we study properties of micro-cavities which incorporate materials that exhibit Electro-magnetically Induced Transparency (EIT) or Ultra Slow Light (USL). We find that such systems, while being miniature in size (order wavelength), and integrable, can have some outstanding properties. In particular, they could have lifetimes orders of magnitude longer than other existing systems, and could exhibit non-linear all-optical switching at single photon power levels. Potential applications include miniature atomic clocks, and all-optical quantum information processing.
The ability of photonic crystals to mold the flow of light in new ways can lead to a variety of novel and improved designs of optical nano-components and nano-devices in photonics. Two examples will be presented: a) Using linear materials, a polarization independent waveguide is designed in a 3D photonic crystal. It is demonstrated that this system provides lossless guiding of light at length-scales approaching the wavelength of the light itself, offering a promising platform for the design of integrated high performance polarization-insensitive waveguide networks. b) Using nonlinear materials, a cylindrical photonic crystal fiber is designed that can exhibit all-optical switching without the need for an axial periodicity. It is shown that this property stems from the unique structure of the cylindrical photonic crystal guided-mode dispersion relation, and can lead to significant improvements in manufacturing ease, operating power usage, and device size requirements, making such a system ideal for integrated all-optical signal processing.