[16a-C301-1~9] 4.4 Opto-electronics

▲ [16a-C301-9] A Theoretical Investigation on Supercontinuum Generation in Saturable Optical Nonlinear Media

〇(D)Kanagaraj Nithyanandan¹ (1.Pondicherry Univ.)

キーワード：Photonic crysal fibers, Supercontnuum generation, Nonlinearity

The supercontinuum is the generation of intense ultra broadband high conherent spectrum spanning over a few octaves . With rapid advancement in photonic crystal fiber technology, supercontinuum gains momentum and evolves as one of the most elegant and dramatic effect in optics with a wide range of potential pplications in various field. The supercontinuum generation is typically achieved by two mechanisms, namely, soliton fission and modulational instability. The soliton fission is found to be a best technique for generating coherent and high quality broadband sources. In recent times, the concept of saturated nonlinearity has deserved much interest due to its inherent nature in all material and owing to its high power operation. To investigate supercontinuum generation in photonic crystal fiber, we numerically solved the modified nonlinear Schrodinger Equation using split step Fourier method. The fiber parameters are calculated using scalar effective index method. From the numerical simulation it is observed that the exponential saturable nonlinear response suppress the supercontinuum generation like the case of conventional saturable nonlinear response. But the inclusion of exponential saturable nonlinearity enables to achieve the broadband spectrum at relatively short distance of propagation owing to the ability to achieve the required phase matching for the nonlinear effects. It is evident that the broadband spectrum obtained through exponential saturable nonlinearity and conventional saturable nonlinearity is approximately the same for the given length. But the coherence obtained through the shot to shot noise analysis gives us the incorporation of exponential saturable nonlinearity instead of conventional saturable nonlinearity increases the coherence of the spectrum slightly. We conclude that the use of exponential nonlinearity like the most cases of saturable nonlinearity suppress the supercontinuum spectrum, but slightly increases the coherence of the supercontinuum generation.