Birefringence Analysis of Directional Fiber Coupler Induced by Fusion and Coupling Parameters

Abstract

The effect of fusion and coupling parameters to the form of birefringence of coupling region directional fiber coupler is reported. Vector of polarization was determined by using perturbation method that describes the propagation of electric field in single mode fiber coupling induced by stress which is caused by fusion and coupling parameters during fabrication. It is found that the radius of coupling cross section, refractive index different, normalized frequency, and twisting angle significantly affect the polarization and birefringence. But, the change of temperature during fusion in range of 27-1350 °C gives small increment in birefringence directional fiber coupler. By knowing these parameters, the polarization and birefringence are possible to maintain and optimize the fiber coupler.