High quality entanglement on a chip-based frequency comb.

We report an efficient energy-time entangled photon-pair source based on four-wave mixing in a CMOS-compatible silicon photonics ring resonator. Thanks to suitable optimization, the source shows a large spectral brightness of 400 pairs of entangled photons /s/MHz for 500 µW pump power, compatible with standard telecom dense wavelength division multiplexers. We demonstrate high-purity energy-time entanglement, i.e., free of photonic noise, with near perfect raw visibilities (> 98%) between various channel pairs in the telecom C-band. Such a compact source stands as a path towards more complex quantum photonic circuits dedicated to quantum communication systems.

Simplified modeling and optimization of silicon modulators based on free-carrier plasma dispersion effect.

In this paper, a simplified model of silicon phase modulators is presented that enables favorable accuracy together with a substantial reduction in computational effort and without the requirement of semiconductor TCAD device simulation software. This permits fast optimization of the different parameters of a modulator. The model was successfully implemented in Phoenix Optodesigner optical software allowing the optimization of silicon phase shifters for different applications. Moreover, this model presents a great potential for the simulation of modulators based on PN interdigitated junctions, which normally require complex and time consuming 3D simulations. Simulation time was reduced by a factor of 6 for the lateral PN junction based modulator, and two orders of magnitude reduction was obtained for interdigitated PN junctions based modulators.

Analytical model for depletion-based silicon modulator simulation.

An original method to simulate depletion-based silicon modulators based on an analytical description of the active region is presented. This method is fast and efficient in particular for performance optimization. It is applied for a lateral diode integrated in a rib waveguide, and a comparison is performed with classical 2D numerical simulation. A very good agreement is obtained, showing the accuracy and efficiency of this analytical method.

Enhancement of semiconducting single-wall carbon-nanotube photoluminescence.

Photoluminescence properties of semiconducting single-wall carbon-nanotube (s-SWNT) thin films with different metallic single-wall carbon-nanotube (m-SWNT) concentrations are reported. s-SWNT purified samples are obtained by polymer-assisted selective extraction. We show that the presence of a few m-SWNTs in the sample generates a drastic quenching of the emission. Therefore, the highly purified s-SWNT film is a strongly luminescent material and a good candidate for future applications in photonics, such as near-IR emitters, modulators, and detectors.

Experimental evidence for superprism phenomena in SOI photonic crystals.

A first experimental demonstration of a planar superprism in silicon microphotonics technology using silicon on insulator (SOI) substrates is presented. Experimental results for anomalous wavelengthdependent angular dispersion in SOI triangular lattice planar photonic crystals are reported. An angular swing of 14 degrees is measured for light propagating near the Gamma-K direction as the input wavelength is changed from 1295 nm to 1330 nm, which corresponds to an angular dispersion of 0.4 degrees /nm. For the Gamma-M direction, a negative wavelength dispersion has been recorded. An opposite sign angular deviation of 21 degrees is observed as the input wavelength is changed from 1316 nm to 1332 nm, i.e. a dispersion of 1.3 degrees /nm.

Low-loss submicrometer silicon-on-insulator rib waveguides and corner mirrors.

Rib microwaveguides are demonstrated on silicon-on-insulator substrates with Si film thickness of either 380 or 200 nm and a width of 1 microm. Corner mirrors that allow compact 90 degrees turns between two perpendicular waveguides are characterized. Measured propagation losses are approximately 0.4 dB/cm and approximately 0.5 dB/cm for 380-nm and 200-nm Si film, respectively, and mirror losses are approximately 1 dB. This allows the development of applications such as optical interconnects in integrated circuits over propagation distances larger than several centimeters.