title: Simple geometric criterion to predict the existence of surface modes in air-core photonic-bandgap fibers.
abstract: We propose a simple geometric criterion based on the size of the core relative to the photonic crystal to quickly determine whether an air-core photonic-bandgap fiber with a given geometry supports surface modes. Comparison to computer simulations show that when applied to fibers with a triangular-pattern cladding and a circular air core, this criterion accurately predicts the existence of a finite number of discrete ranges of core radii that support no surface modes. This valuable tool obviates the need for time-consuming and costly simulations, and it can be easily applied to fibers with an arbitrary photonic-crystal structure and core profile.
authors.forename: Michel
authors.initials: M
authors.lastname: Digonnet
authors.forename: Hyang
authors.initials: H
authors.lastname: Kim
authors.forename: Jonghwa
authors.initials: J
authors.lastname: Shin
authors.forename: Shanhui
authors.initials: S
authors.lastname: Fan
authors.forename: Gordon
authors.initials: G
authors.lastname: Kino