Professor Jianji Dong and his group of optoelectric devices and integration functional laboratory of Wuhan National Laboratory for Optoelectronics proposed a silicon-on-insulator (SOI) on chip optical arbitrary waveform generator, which is based on Taylor synthesis method. Unlike other schemes based on Fourier synthesis method, we control the amplitude and phase of the differential waveform (Taylor series in time domain) of each tap instead of optical frequency comb lines.

This new research (Photonic arbitrary waveform generator based on Taylor synthesis method) has been published in Optics Express in 17 October.

In our scheme, a Gaussian pulse is launched to some cascaded microrings to obtain first-, second- and third-order differentiations. By thermally adjusting amplitude and phase of the initial pulse and successive differentiations, we can realize an arbitrary waveform generator according to Taylor expansion. We obtain several typical waveforms such as square waveform, triangular waveform, flat-top waveform, sawtooth waveform, Gaussian waveform and so on. This scheme has distinct advantages of compactness, small power consumption and capability for integration with electronics. Optical arbitrary waveform generation (OAWG) plays a critical role in many applications, such as generating optical ultra-wide band (UWB) signal, optical pulse radar, and test of optical communication system. So this new research achievement has wide application prospects.

Several researchers including Prof. Xinliang Zhang, Prof. Jianji Dong, and Shasha Liao, etc. in Wuhan National Lab for Optoelectronics and Yunhong Ding in Technical University of Denmark have contributed in this research.

This work was supported in part by New Century Excellent Talents in Ministry of Education of China (NCET-11-0168), National Excellent Doctoral Dissertation of China (201139), National Natural Science Foundation of China (NSFC) (61622502, 61475052).

Fig. 1 Metallurgical microscopy image of the on-chip pulse shaper, (a) whole graph, details of (b) MZI and (c) MRR.