Photonic crystal waveguides and cavities in integrated optics
Laboratory of Photonics and Microwave Engineering (FMI)
Department of Microelectronics and Information Technology (IMIT)
Royal Institute of Technology (KTH)
Electrum 229, 164 40 Kista
Two-dimensional Photonic crystal (2D PC) waveguides and cavities are key
elements in photonic crystal based integrated. Devices based on
2D PCs are typically realized as 3D structures consisting of an array of
holes (or rods) vertically etched through a slab waveguide.
The existence of holes in a slab waveguide may induce strong radiation
losses to the slab claddings. By employing the 2D finite-difference
time-domain method, and the effective-index method to account for the
vertical confinement, we show that a remarkably good agreement with
experiments can be obtained, for a number of experimentally studied PC
structures (cavities, waveguides and bends).
Many of PC waveguides are multi-mode, thus the coupling between the
different guided modes are of interests. Mode-gaps (or mini-stop-bands)
may arise from Bragg diffraction of the incident mode into the
counter-propagating modes. In the talk, we also present the
experimental characterization and theoretical calculations of
mini-stop-bands, which are important to accurately design and
fabricate of PCs.