Modified Plus Shaped Photonic Crystal Fiber Structure with Low Loss, Negative Dispersion and High Birefringence over S+C+L Wavelength Bands

Nowadays, Photonic Crystal Fiber (PCF) based structures have become a profound research interest worldwide and have been widely applied in many fields because of their flexible and controllable characteristics. Photonic Crystal Fiber is an individual category of optical fiber having periodic air holes in the cladding. A new PCF structure is proposed having modified plus shaped geometry also having multiple defects of two different shapes-circular and elliptical. Confinement loss, dispersion and birefringence performance of the structure is analyzed. Low loss with small but non-zero dispersion for both defects is obtained at the telecommunication optical wavelength (S+C+L) bands. The structure also offers high birefringence of 4.77×10^-2 at 1.55μm operating wavelength. Structure design and simulation have been carried out adopting COMSOL Multiphysics software based on the full vectorial finite element method (FEM) with perfectly matched layer (PML) boundary conditions. The structure can be considered as a viable option for optical sensing and optical communication systems like, long-haul data transmission, wavelength division multiplexing (WDM) and many others.