• Barth, C.; Wolters, J.; Schell, A.W.; Probst, J.; Schoengen, M.; Löchel, B.; Kowarik, S.; Benson, O.: Miniaturized Bragg-grating couplers for SiN-photonic crystal slabs. Optics Express 23 (2015), p. 9803-9811

10.1364/OE.23.009803
Open Access Version

Abstract:
We report on an experimental and theoretical investigation of an integrated Bragg-like grating coupler for near-vertical scattering of light from photonic crystal waveguides with an ultra-small footprint of a few lattice constants only. Using frequency-resolved measurements, we find the directional properties of the scattered radiation and prove that the coupler shows a good performance over the complete photonic bandgap. The results compare well to analytical considerations regarding 1d-scattering phenomena as well as to FDTD simulations.