title: Vector description of higher-order modes in photonic crystal fibers
abstract: We extensively study the propagation features of higher-order modes in a photonic crystal fiber (PCF). Our analysis is based on a full-vector modal technique specially adapted to accurately describe light propagation in PCF's. Unlike conventional fibers, PCF's exhibit a somewhat unusual mechanism for the generation of higher-order modes. Accordingly, PCF's are characterized by the constancy of the number of modes below a wavelength threshold. An explicit verification of this property is given through a complete analysis of the dispersion relations of higher-order modes in terms of the structural parameters of this kind of fiber. The transverse irradiance distributions for some of these higher-order modes are also presented, showing an excellent agreement with recent experimental measurements. In the same way, the full-vector nature of our approach allows us to analyze the rich polarization structure of the PCF mode spectrum.
authors.affiliation: Departament d'Optica, Universitat de Valencia, Burjassot, Spain. albert.ferrando@uv.es
authors.initials: A
authors.lastname: Ferrando
authors.initials: E
authors.lastname: Silvestre
authors.initials: JJ
authors.lastname: Miret
authors.initials: P
authors.lastname: Andres