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.

Symmetry and degeneracy in microstructured optical fibers

“…Some authors (see, e.g., Ref. 5) have explicitly stated that these modes have different propagation constants, i.e., that they are nondegenerate. Others have referred to them as constituting a "doublet" but without defining this term rigorously.…”

Stack and draw fabrication of soft glass microstructured fiber optics

“…Designing of photonic crystal fibers presented in this review was done at the Information Optics Group of Faculty of Physics at University of Warsaw. In the simulations a full vector method of biorthonormal basis, derived from the works of Silvestre et al [6][7][8], has been used, where a matrix representation of the vector wave equations is calculated on the basis of plane waves and an eigenvalue problem is solved for that matrix. The vector wave equations involve a pair of Hermitian-conjugate operators whose eigenvectors satisfy the bi-orthonormality relations.…”

Guiding Properties of a Photonic Quasi-Crystal Fiber Based on the Thue–Morse Sequence

“…The most common PCFs comprises a triangular lattice with a defect generated by the absence of a hole [5]. In this case, donor guided modes appear simultaneously in the upper and the lower forbidden bands of the triangular photonic crystal [6]. Alternatively, guidance 1 is also possible in honeycomb fibers in which the defect is generated by an extra hole located off the lattice.…”