QPSK Modulation in the O-Band Using a Single Dual-Drive Mach Zehnder Silicon Modulator

[EN] Keeping up with bandwidth requirements in next generation short- and long-reach optical communication systems will require migrating from simple modulation formats such as on-off keying to more advanced formats such as quaternary phase-shift keying (QPSK). In this paper, we report the first demonstration of QPSK signal generation in the O-band using a silicon dual-drive Mach-Zehnder modulator (DD-MZM). The performance of the silicon DD-MZM is assessed at 20 Gb/s and compared against a similar DD-MZM based on LiNbO3, showing a limited implementation power penalty of only 1.5 dB.This work was supported in part by the European project Plat4m (FP7-2012-318178); European project Cosmicc (H2020-ICT-27-2015- 688516); French Industry Ministry Nano2017 program.Pérez-Galacho, D.; Bramerie, L.; Baudot, C.; Chaibi, M.; Messaoudène, S.; Vulliet, N.; Vivien, L.... (2018). QPSK Modulation in the O-Band Using a Single Dual-Drive Mach Zehnder Silicon Modulator. Journal of Lightwave Technology. 36(18):3935-3940. https://doi.org/10.1109/JLT.2018.2851370S39353940361

Community action: value or instrument? An ethics and planning critical review

The community concept has maintained a constant and growing interest in urban studies and many related fields. The origin of this continuing interest seems to derive from the importance of the concept of community within diverse forms of political language and interpretations within different planning practices. In this contribution, through the analysis of different ethical and planning theories, we want to provide an update framework on community action. According to this objective, the argumentation will proceed through a literature review on four ethics theories and three key aspects related to spatial planning, as well as matching this theoretical analysis with exemplifying practices. The final objective is to provide an original analysis on drivers and outcomesof different forms of community, raising general issues that refer to spatial planning, social organization and regulation

Developments in 300mm Low-Power Si Capacitive Modulators Invited paper

International audienceWe report on the development of high speed phase shifters for next generation of Si photonics transceivers, based on capacitive structures. Experimental measurements show a VL of 0.5V.cm in accumulation regime. We also show that the addition of a SiGe layer at the capacitive interface leads to an improvement of 25 % of the phase shifter efficiency