Abstract:
Optical fiber based wavelength division multiplexing (WDM) is widely used to satisfy the high
bandwidth demand using optical network. But dispersion, non-linearity and attenuation restrict the
wavelength region and transmission bit rate for conventional fiber. Photonic crystal fibers (PCFs) are
micro-structured optical fiber which are constructed by single material with multiple air holes
periodically arranged around the core. PCFs have ability to be single mode over a broad range of
wavelengths. Large number of available design parameters of solid core PCF makes the dispersion,
nonlinearity and confinement loss highly configurable. PCFs are of great interest for optical
communication in new wavelength regions and for new optical devices. As the stress and thermal
effect on PCFs can alter the propagation properties significantly, it is very important to know and
study the properties of PCF to fully understand the feasibility of using it as sensor for stress civil
structures or acoustic pressure in underwater and underground communication systems. In this
research work the effect of external stress and design parameters on propagation properties for
square, hexagonal and octagonal air-hole arranged PCFs have been analyzed and simulated. The
fiber designs are carried out for all types of PCFs by varying number of air hole rings and air hole
diameter and different amount of stress is applied on the PCFs boundary and the effective indices,
birefringence are calculated as a function of stress. It is found that external stress on PCF causes
stress distribution and fiber deformation in fiber cross section. This deformation is not same for all
type of fibers and in all direction (x and y), which causes different effective index and birefringence
for all types of PCFs. Results show that external stress affects more on propagation properties of
hexagonal PCF than square or octagonal and this effect is lower for larger number of air hole rings
and air hole diameter. Our findings will help to find the appropriate designing of PCF for some of
particular application.
