Simulation of Traveling Wave Electroabsorption Modulators Suitable for 100Gbps
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
The large signal model for electro-absorption modulators is studied and simulated. In the previous model, the effect of frequency chirp has not been included and also there is no phase information of the optical carrier.
This thesis focuses on introducing the phase information of the optical carrier by representing it as a time varying sinusoidal voltage as well as modeling frequency chirp in traveling wave electro-absorption modulators by using a voltage dependent transmission line delay. The transmission line is designed as periodic LC section, where all the capacitance values were modeled to have a quadratic dependence on the microwave voltage using the CBREAK model in PSPICE. This means that the transmission line delay will have a linear dependence on the voltage.
The whole modified model for the modulator is then simulated and the frequency chirp effect on the modulator performance was studied. It is shown that the frequency chirp broadens the modulator spectrum but it has no pronounced effect on the eye diagram. This means that long distance transmission will be mutilated due to dispersion.
By choosing a small absorption and large change in delay, the phase modulator is simulated and can be fabricated by using a three step quantum well because it has a large change in refractive index and small change in absorption. On the other hand, to fabricate an electro-absorption modulator a rectangular quantum well should be used.
Place, publisher, year, edition, pages
2011. , 42 p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-96942OAI: oai:DiVA.org:kth-96942DiVA: diva2:533304
Subject / course
Microelectronics and Applied Physics
Master of Science - Photonics
Westergren, Urban, Professor
Hemani, Ahmed, Professor