Periodic Modulation of Nonlinearity in a Two-Core Photonic Crystal Fiber: A Numerical Investigation

A. F. G. F. Filho^1*, A. G. L. S. O. Mendes¹, J. R. R. Sousa^1,2, G. S. Batista¹, A. M. Bastos^1,2, C. S. Sobrinho¹, M. L. Lyra³, A. S. B. Sombra^1,2

¹Laboratório de Telecomunicacoes e Ciência e Engenharia de Materiais LOCEM, Departamento de Física, Universidade Federal do Ceará, Ceará, Brazil.
²Departamento de Engenharia de Teleinformática (DETI), Centro de Tecnologia, Universidade Federal do Ceará, Ceará, Brazil.
³Instituto de Física, Universidade Federal de Alagoas, Maceió, Brazil.

DOI: 10.4236/jemaa.2015.72005                

Abstract

We present a numerical investigation of the propagation and the switching of ultra-short pulses (100 fs) in a two-core nonlinear coupler of photonic crystal fibers constructed with periodically modulated the non-linearity fiber (PMNL-PFC). Our simulations are taking into account different amplitude and frequency modulations of the PMNL-PFC. A coupler for coupling whose length is L_c = 1.8 cm, the transmission characteristics, the compression factor, the crosstalk (Xtalk) and extinction ratio (Xratio) levels of the first order solitons were studied for low to high pump energies considering 2L_c. By an analysis on the reference channel (channel 2), it is observed that at low modulation frequencies an increase occurs in the switching power increasing transmission efficiency. For high modulation frequencies, the transmitted energy efficiency loses. The switching pulses are stronger for low frequency and high amplitude modulation. The Xtalk is a function of the measurement made on the secondary channel (channel 1). It was observed that this unwanted high-frequency energy increases to lessen the measure of the amplitude modulation. In summary, we have demonstrated that introduction of a non-linearity profile takes the periodically modulated PMNL-PFC to strong variations at transmission efficiency, Xtalk, Xratio a function of frequency and modulation amplitude and the input power.

Keywords

Coupler of Photonic Crystal Fibers, Periodically Modulated the Non-Linearity, Two-Core Nonlinear, Crosstalk Level, Extinction Ratio Level

Conflicts of Interest

The authors declare no conflicts of interest.

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