TOPIC (1) :

Cross Waveguide Resonator-Based Silicon Electro-Optic Modulators

SPEAKER (1)

Mr Xin Maoqing, Graduate Student

Dept of Electrical & Computer Engineering, NUS

TIME (1) :

2.00 pm  to  2.40 pm

ABSTRACT (1) :

High speed optical modulators have been playing a key role in optical communication systems with high transmission capacities. In order to leverage the well established complementary metal-oxide-semiconductor (CMOS) technology, silicon on insulator (SOI) systems have attracted intense research interests for realizing nanophotonic devices [1-7] due to the high index contrast between silicon and substrate. In this talk, we propose a cross waveguide resonator structure and apply it to a conventional carrier injection mode silicon modulator. This new configuration enables a much higher modulation speed by introducing a more efficient carrier injection scheme. According to our numerical study results, the peak modulation speed hits 2.9 GHz at a low DC power consumption of 17.3 mW and even higher modulation speed is possible by employing alternative index perturbation modes such as accumulation or depletion mode.

BIOGRAPHY (1)

Mr. Xin Maoqing obtained his B.Eng degree from Department of Electronic Engineering, Shanghai Jiao Tong University, China in 2007. He is currently pursuing a PhD degree at Center for Optoelectronics, Department of Electrical and Computer Engineering, National University of Singapore. His research interest focuses on the silicon photonic band gap waveguides and modulators.

TOPIC (2) :

Multi-channel 80-GHz Pulse Train Generation Based on Optical Parametric Process in HNLF

SPEAKER (2)

Ms Yang Jin, Graduate Student

Dept of Electrical & Computer Engineering, NUS

TIME (2):

2.50 pm  to  3.40 pm

ABSTRACT (2) :

An invaluable element for high-speed optical communication systems is a return-to-zero (RZ) optical pulse train generator at the data clock speed or bit rate. The most common method to generate high-speed pulse train is using a mode-locked laser, which is for a single channel and the tuning range of the wavelength is very limited.  For WDM applications, it will require several expensive mode-locked lasers which are not affordable for real systems and most labs. Fiber optical parametric process has many applications in high-speed optical communication systems, since it can provide high gain over a wide bandwidth. It can be used to realize optical amplifier, wavelength converter, and also multi-channel pulse generation.

In this talk, 6-channel 80-GHz pulse trains generation in 1-km highly nonlinear fiber (HNLF) based on optical parametric effect will be shown. 3-channel C-band continuous-wave (CW) channels are amplified by the pulsed pump and become pulse trains. At the same time, 3-channel pulse trains are generated at the converted L-band idler wavelengths. The generated 6-channel pulse trains have nearly the same pulse widths and can be used as the source of WDM systems.

BIOGRAPHY (2)

Miss Yang Jing received her Bachelor degree in Electrical Engineering from Xi’an Jiaotong University, China, in 2005. She is currently pursuing her PhD degree in Department of Electrical & Computer Engineering, NUS. Her research interest is fiber physical effects in high-speed optical communication network and fiber sensor system.