Pixelated Bragg fibers: bandgap guiding, generalized half-wave stack condition, and application to large mode area fibers

Bandgap formation in pixelated Bragg fibers is explained by using the plane wave expansion method. A generalization of the half-wave stack condition is proposed and exploited by using a pixelated ring heterostructuration. Such fibers open up the way to designing new single-mode large mode area (LMA) fibers. A single-mode LMA fiber with a core diameter of 50 μm that is composed of only two rings of high-index rods is used as an example.