Complex long-period-grating-assisted-coupler and its application in optical signal buffer

Abstract

By introducing gain/loss perturbation into periodic refractive index modulation, the unified coupled-mode equations and their close-form analytical solutions of complex long-period-grating-assisted-coupler (LPGAC) are deduced. Characteristics of power coupling are investigated and results show that unidirectional nonreciprocal signal transferring can be achieved by matching gain/loss with the refractive index modulation. Utilizing the feature of complex LPGAC, a novel optical signal buffer is proposed and its structure is examined in detail.

Keywords

optical device / long-period-grating-assisted-coupler / optical signal buffer / complex-modulated-grating

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Acknowledgements

This work was jointly supported by the National Natural Science Foundation of China (Grant No. 61007007) and the Fundamental Research Funds for the Central Universities of China (No. 2011JBM014).

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg