Distortion-corrected phase demodulation using phase-generated carrier with multitone mixing.

We present a novel phase generated carrier (PGC) demodulation technique for homodyne interferometers which is robust to modulation depth variations and source intensity fluctuations. By digitally mixing the waveform with a multitone synthetic function (a linear combination of harmonics of the modulating signal), distortion can become negligible even in presence of large variations of the modulation depth. The technique only requires two mixers and can also provide the DC component of the phase in real time, without needing any previously recorded data or ellipse-fitting algorithms.

Geometrical Representation of a Polarisation Management Component on a SOI Platform.

Grating couplers, widely used in Silicon Photonics (SiPho) for fibre-chip coupling are polarisation sensitive components, consequently any polarisation fluctuation from the fibre optical link results in spurious intensity swings. A polarisation management componentis analytically considered, coupled with a geometrical representation based on phasors and Poincaré sphere, generalising and simplifying the treatment and understanding of its functionalities. A specific implementation in SOI is shown both as polarisation compensator and polarisation controller, focusing on the operative principle.

Polarization insensitive silicon photonic ROADM with selectable communication direction for radio access networks.

We report on an experimental prototype of a low-cost silicon photonic reconfigurable optical add/drop multiplexer (ROADM). The device is able to operate with up to 12 wavelength division multiplexing channels. In order to control the polarization of the multi-wavelength signal at the input of the device, an integrated polarization controller is investigated as an alternative to the polarization diversity device architecture.

Photo-induced trimming of chalcogenide-assisted silicon waveguides.

A chalcogenide-assisted silicon waveguide is realized by depositing a thin layer of A(2)S(3) glass onto a conventional silicon on insulator optical waveguide. The photosensitivity of the chalcogenide is exploited to locally change the optical properties of the waveguide through exposure to visible light radiation. Waveguide trimming is experimentally demonstrated by permanently shifting the resonant wavelength of a microring resonator by 6.

A near-field actuated optical nanocavity.

We demonstrate here that switching and tuning of a nanocavity resonance can be achieved by approaching a sub-micrometer tip inside its evanescent near-field. The resonance energy is tuned over a wide spectral range (Deltalambda/lambda~10(-3)) without significant deterioration of the cavity peak-transmittance and of the resonance linewidth. Such a result is achieved by taking benefits from a weak tip-cavity interaction regime in which the tip behaves as a pure optical path length modulator.