Scanning of the bands of a microstructured fiber via its bending

The propagation-constant bands responsible for the loss in a microstructured quartz fiber with a cladding in the form of a periodic hexagonal hole structure and with a core in the form of a missing hole are investigated theoretically and experimentally. The theory is based on a new model of the cladding, which is represented as a set of strongly coupled optical waveguides of a triangular cross section. The strong coupling results in splitting of the propagation constants of these optical waveguides into bands. In the experiment, a new technique for scanning these bands is proposed and realized for the case when the fiber has a bend with a variable radius. The theory provides for an adequate description of the results.[PUBLICATION ABSTRACT]