Asymmetric directional couplers based on silicon nanophotonic waveguides and applications

Daoxin DAI, Shipeng WANG

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Front. Optoelectron. ›› 2016, Vol. 9 ›› Issue (3) : 450-465. DOI: 10.1007/s12200-016-0557-8
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REVIEW ARTICLE

Asymmetric directional couplers based on silicon nanophotonic waveguides and applications

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Abstract

Directional couplers (DCs) have been playing an important role as a basic element for realizing power exchange. Previously most work was focused on symmetric DCs and little work was reported for asymmetric directional couplers (ADCs). In recently years, silicon nanophotonic waveguides with ultra-high index contrast and ultra-small cross section have been developed very well and it has been shown that ADCs based on silicon-on-insulator (SOI) nanophotonic waveguides have some unique ability for polarization-selective coupling as well as mode-selective coupling, which are respectively very important for polarization-related systems and mode-division-mulitplexing systems. In this paper, a review is given for the recent progresses on silicon-based ADCs and the applications for power splitting, polarization beam splitting, as well as mode conversion/(de)multiplexing.

Keywords

silicon photonics / asymmetric directional couplers (ADCs) / polarization-division multiplexing (PDM) / mode-division multiplexing (MDM) / polarization beam splitter (PBSs)

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Daoxin DAI, Shipeng WANG. Asymmetric directional couplers based on silicon nanophotonic waveguides and applications. Front. Optoelectron., 2016, 9(3): 450‒465 https://doi.org/10.1007/s12200-016-0557-8

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Acknowledgement

We thank Dr. Jian Wang, Dr. Pengxin Chen, Dr. Xiaowei Guan, Dr. Fei Lou, Prof. Lech Wosinski, Dr. Di Liang, Prof. John Bowers, Dr. Yaocheng Shi, Prof. Sailing He, et al for their contributions and the support from the National Natural Science Foundation of China (NSFC) (Grant Nos. 11374263, 6141101056, 61422510), the Doctoral Fund of Ministry of Education of China (No. 20120101110094), and the Fundamental Research Funds for the Central Universities.

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