title: Gratings superposed spatially by writing in laterally separated regions.
abstract: A new type of gratings superposed spatially in laterally separated areas of the guide is introduced and analyzed using coupled-mode theory. The guided mode overlaps the constituent gratings and sees the superposition of them. Also, special characteristics that the structure might synthesize are considered, including one example where a phase-only sampled split grating provides zero response for out-of-band channels. A conventional grating requires both phase- and amplitude- sampling for zero out-of-band channels. The split grating, however, requires alignment of the constituent gratings in addition to requirements on the accuracy of the amplitude and pitch structures.
authors.forename: Thomas
authors.initials: T
authors.lastname: Gradishar
authors.forename: A
authors.initials: A
authors.lastname: Safaai-Jazi