Comparison of Chiral and Conventional Long Period Fiber Gratings

The properties of mode couplings in chiral long period gratings (CLPGs) and conventional uniform long period gratings (LPGs), including the mode selective rules, polarization selectivity and coupling strengths, are analyzed for comparison, by using the coupled-mode theory. For a CLPG, whether a mode coupling is polarization-selective or not depends on different mode selective rules. While for a uniform LPG, it is polarization-unselective. In addition, the coupling strengths for CLPGs are usually several times larger than those for LPGs. On the other hand, the fabrications of CLPGs and conventional LPGs are compared. The polymer CLPGs are also suggested with their potential advantages.