Second-order optical differentiator using mechanically-induced LPFG with a single π-shift

Abstract

An all-optical second-order temporal differentiator using a mechanically-induced long-period fiber grating (MI-LPFG) with a single π-shift was demonstrated. The MI-LPFG was created by pressing a fiber between two periodically grooved plates with a π-shift located at the 3/4 length from the input end of LPFG. The coupling coefficient (κ) can be adjusted by changing the pressure applied on the fiber. The experimental results show that the transfer function of the proposed MI-LPFG can be adjusted to have a transfer function as an ideal second-order differentiator. The differential performance of the designed differentiator to a Gaussian pulse is also analyzed.

Keywords

optical differentiator / long-period fiber-grating (LPFG) / optical signal processing

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant Nos. 60925019 and 61090393). This work was also partially supported by the Fundamental Research Funds for the Central University (No. ZYGX2009Z002).

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg