Photonic crystal fiber analysis through the vector boundary-element method: effect of elliptical air hole

An efficient numerical approach based on the vector boundary-element method is employed to investigate the propagation characteristics of the elliptical air holes photonic crystal fibers (EPCF). The effect of elliptical air holes on the birefringence and dispersion properties is presented. Two types of EPCF structure are defined and four corresponding guided modes with a different effective index are solved. Besides showing significant birefringence and flattened dispersion properties of the EPCF, the study finds that among these four modes, the dispersion is significantly larger for the mode with smaller effective index.