NOVEL SLAB MODEL ANALYSIS FOR OVERLAYER DEPOSITED BENT STEP-INDEX SINGLE-MODE FIBER HALF-COUPLERS

A Novel Slab Model (NSM) for the modal analysis of Overlayer (OL) depo sited Bent Step-index Single-Mode Fiber (BSSF) half-couplers is presen ted. In this NSM the BSSF is replaced by a modal equivalent slab waveg uide (ESW) structure. It is shown that within the framework of the NSM the modal features of actual OL-BSSF structures can be described more correctly and consistently on the basis of equivalent OL-ESW structur es. A perturbation method is developed to analyze modal properties of such OL-ESW structures analytically. Our modal analysis comprises all hitherto investigated evanescent fiber-optic devices based on OL-BSSF structures.