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We report crosstalk measurements among spatially-multiplexed subchannels in a ROADM supporting spatial superchannels. Aggregate crosstalk can reach -23dB when express paths are routed on adjacent fibers, but >6dB improvement results when paths are interleaved.

We present the technological merits of combining a high fill factor, one-dimensional, MEMS micro-mirror array for switching and liquid crystal shutters for amplitude control within a wavelength-selective switch (WSS). The combination allows for simplified MEMS actuator design, support for high port counts, high attenuation accuracy, high natural frequency, mechanical robustness against shock & vibrations, and fast switching times. The complexity associated with dual modulating elements at the focal plane is addressed by design choices and optimization of the depth of focus. The WSS is fully Telcordia qualified and carrying live traffic in deployed networks.

Optical switching fabrics based on 3D MEMS technology potentially offer a scalable solution for the cross-connect network element. The design, integration, and assembly of high port count switch fabrics that can operate under a low loss budget, fast switching time, superb mirror stability and long-term reliable packaging present important engineering challenges. In this paper we describe the major optical, mechanical, MEMS and electronic design considerations as well as their critical inter-relationships in the development of 3D MEMS-based optical cross-connect fabrics. The specifications placed on the various components in order to meet the overall system tolerances and loss budget will be discussed. In addition, we will address the short-term (sub-millisecond) control and long-term (hours and up) stability of the optical connections due to mirror stability and long-term mechanical drifts. We will also present our thoughts regarding the solutions to those problems.

A tunable coherent far infrared radiation source from a biased semiconductor microcavity is demonstrated. The radiation is emitted after resonant excitation of the cavity polaritons by a short laser pulse and its energy is tuned by applying different bias fields.