Research And Application Of Photonic Crystal Fibers In Supercontinuum Generation

The emergence of Photonic Crystals(PC) bring the innovation of the development of optical devices and optical networks. After the electronic semiconductor era which has promoted scientific progress of the whole community, the photon era is just around the corner. Photonic Crystals has similar properties with electron in many respects. So we can research Photonic Crystals by referring to some electronic research methods. This paper mainly demonstrates the computation of photonic bandgap in Photonic Crystals and the application of Photonic Crystal Fibers(PCF) in supercontinuum generation.Theoretical research methods of Photonic Crystals include Plane-Wave Expansion Method, Finite-difference time-domain (FDTD), Transfer Matrix Method and other methods. Among all these methods the most commonly and widely used is Plane-Wave Expansion Method. And the simplest structure of Photonic Crystals is the square structure of cylindrical medium. Then this paper introduces the research in this structure with Plane-Wave Expansion Method. Subsequently two special two-dimensional square-cycle Photonic Crystals are introduced. By numerical analysis, a wide Photonic Bandgap is found in such Photonic Crystals. And this provides us a new research way of searching wide Photonic Bandgap.PCF is a special application of two-dimensional Photonic Crystals. It is of great significant not only in optical communications, but also for many optical devices. By the equivalent-refractive index model, this paper has researched the relationship between the cladding equivalent-refractive index and structural parameters of photonic crystal fibers (PCF).The value of the normalized frequency V is influenced by the structural parameters of PCFs. That can explain the endlessly single-mode transmission. Then in analogy with the theory of step-index fibers, the effective index of the fundamental mode and the dispersion of PCF can be calculated simply. Finally, we also researched supercontinuum generation in PCF. The numerical analysis shows that the pulse spectrum is widened remarkably. And a new research approach is presented, which finding the input spectrum with given output spectrum and structure of PCF.