1.
Opt Express
; 27(11): 15856-15867, 2019 May 27.
Article
in English
| MEDLINE
| ID: mdl-31163775
ABSTRACT
We present the design, modeling, fabrication, and characterization of grating coupler devices for z-cut lithium niobate near 1550 nm. We first experimentally measure the sensitivity of the insertion loss of a conventional grating coupler to translational misalignment through a three-factor full factorial design of experiment. Next, we design grating couplers that are significantly less sensitive to misalignment. The fabricated devices experienced less than 7 dB of excess insertion loss for combined misalignments of up to ± 5 µm in plane and up to -2 µm or + 10 µm out of plane.