Theoretical Investigation of Bandwidth in Multimode Step-Index Silica Photonic Crystal Fibers

Abstract

Solving the time-dependent power flow equation (PFE) provides a useful method to study the transmission bandwidth of step-index silica photonic crystal fibers (SI SPCFs). The transmission bandwidth of these kinds of fibers is determined for different air-hole structures (different numerical apertures (NAs)) and different distribution widths of the Gaussian launch beam. The results indicate that the lower the NA of SI SPCFs, the higher the bandwidth (for example, for a lower NA of SI SPCFs, a bandwidth that is eight times larger is obtained at a fiber length of 3500 m). The narrower launch beam at short fiber lengths results in a wider bandwidth. The longer the fiber (>300 m), the much less the effect of the launch beam width on the bandwidth. The bandwidth becomes independent of the width of the launch beam distribution at the fiber length at which a steady-state distribution (SSD) is reached. These results are useful for some potential applications, such as high capacity transmission optical fiber systems.

Power Flow in Multimode Graded-Index Microstructured Polymer Optical Fibers

“…One should note that in modeling optical fibers with a GI distribution, it is commonly assumed that D is constant, i.e., it is independent of m [ 31 ]. The same assumption of mode-independent D is also used in modeling step-index microstructured polymer optical fibers [ 33 , 34 ].…”

“…However, it has a z −1/2 dependence beyond this equilibrium length L c . The faster shift to the phase of slower bandwidth decrease would therefore result from the shorter L c [ 29 , 34 ]. A quicker bandwidth enhancement in the examined mPOF is expected compared to conventional GI POFs, demonstrating that GI mPOFs are a superior option for short-range telecommunication lines since the lengths needed to establish an EMD and SSD in GI mPOFs are less than in conventional GI POFs [ 31 ].…”

Improving Temperature-Sensing Performance of Photonic Crystal Fiber via External Metal-Coated Trapezoidal-Shaped Surface

“…Most of the energy in the core region is coupled to the metallic surface, and the energy in the core region decreases rapidly [30]. This phenomenon is characterized by confinement loss (CL) in the PCF, and CL increases sharply as the resonance wavelength increases [31]. Compared to traditional PCFs, SPR-PCF sensors have higher sensitivity and narrower full width at half maximum (FWHM), making them more advantageous.…”

Design of a Novel 1x4 Two-Dimensional Demultiplexer Based on Multicore Photonic Crystal Fiber

“…NEW family of optical waveguides known as photonic crystal fibers (PCFs) has recently received significant research and commercial interest [1][2][3]. PCFs are silica or polymer microstructured waveguides with plenty of air holes positioned in the cladding area of the fiber [4]. In PCFs, light can be steered either by the photonic band gap (PBG) phenomena [5,6] or through the effective index mechanism connected to the modified total internal reflection (MTIR) [7,8].…”