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Current communication networks needs to keep up with the exponential growth of today’s internet traffic, and telecommunications industry is looking for radically new integrated photonics components for new generation optical networks. We at National Research Council (NRC) Canada have successfully developed nanostructure InAs/InP quantum dot (QD) coherence comb lasers (CCLs) around 1.55 m. Unlike uniform semiconductor layers in most telecommunication lasers, in these QD CCLs light is emitted and amplified by millions of semiconductor QDs less than 60 nm in diameter. Each QD acts like an isolated light source acting independently of its neighbours, and each QD emits light at its own unique wavelength. The end result is a QD CCL is more stable and has ultra-low timing jitter. But most importantly, a single QD CCL can simultaneously produce 50 or more separate laser beams at distinct wavelengths over the telecommunications C-band. Utilizing those unique properties we have put considerable effort well to design, grow and fabricate InAs/InP QD gain materials. After our integrated packaging and using electrical feedback-loop control systems, we have successfully demonstrated ultra-low intensity and phase noise, frequency-stabilized integrated QD CCLs with the repetition rates from 10 GHz to 100 GHz and the total output power up to 60 mW at room temperature. We have investigated their relative intensity noises, phase noises, RF beating signals and other performance of both filtered individual channel and the whole CCLs. Those highly phase-coherence comb lasers are the promising candidates for flexible bandwidth terabit coherent optical networks and signal processing applications., SPIE OPTO, Jan. 28 - Feb. 2 2017, San Francisco, California, United States, Series: Proceedings of SPIE; no. 10107

An improved compact 1x2 digital optical switch (DOS) in InGaAsP/InP is studied, and the experimental results are compared to numerical modeling. We present measurements of Mach-Zehnder and DOS devices fabricated with InGaAsP cores having bandgap energies corresponding to wavelengths of 1.2 um, 1.3 um, and 1.4 um. The results are compared with modeling evaluation of refractive index change versus carrier concentration in the different InGaAsP alloys. The effects of modifications in the wafer layer structure are presented as well. Switching current is significantly reduced from greater than 100 mA to about 20 mA, resulting in significant power savings, and in addition eliminating thermal overshoot in the switched optical pulse. The DOS has a measured switching contrast ratio of better than 12 dB with a switching rise time of less than 10 nsec., SPIE Photonics North SPIE, 2004, Series: Proceedings of SPIE