Analysis of waveguide dispersion characteristics of WI- and WII-type triple-clad single-mode fibers

Waveguide dispersion characteristics of two kinds of triple-clad single-mode fibers named WI and WII were examined in this paper. In view of the impossibility to deduce the expression of waveguide dispersion directly due to the complexity of the characteristic equations, a feasible approach to calculate waveguide dispersion was established. The calculated results indicate that the adjustable range of the zero-dispersion point of the triple-clad WI- and WII-type single-mode fibers is obviously wider than that of the conventional doubly clad W-type single-mode fibers in the same conditions. The influences made by the geometric parameters and optical parameters on the waveguide dispersion and cutoff characteristics of low-order modes for WI- and WII-type fibers were analyzed. The method presented to calculate waveguide dispersion can be applied to multi-clad fibers.