High birefringence rectangular-hole photonic crystal fiber

• Birefringent photonic crystal fiber (PCF) based on rectangular-hole is proposed.
• The influence of parameters on birefringence is investigated in rectangular-hole PCF.
• The influence of relative parameters on birefringence is analyzed in three PCFs.
• The birefringences are analyzed at four common wavelengths.

A novel highly birefringent photonic crystal fiber (PCF) based on rectangular-hole is proposed and numerically analyzed by employing the finite-element method. The proposed PCF can achieve birefringences similar to those of the elliptical-hole PCF and rhombic-hole PCF. The properties of such PCFs are investigated for different parameters related to rectangular-holes, including the rectangular-hole pitch, length and the length and width ratio. The results show that the birefringence of rectangular-hole PCF reaches the magnitude of 10−3 which fulfills the requirements of high precision applications in optical systems, which will find application in nonlinear optics.