Design of broadband subwavelength grating couplers with low back reflection
Publication Type:Journal Article
Source:Optics Letters, OSA, Volume 40, Number 20, p.4647--4650 (2015)
Keywords:Gratings; Effective medium theory ; Subwavelength structures
We present a methodology to design broadband grating couplers using one-dimensional subwavelength gratings. Using the presented method, we design subwavelength grating couplers (SWGCs) with 1-dB bandwidths ranging from 50 to 90\&\#xA0;nm. Our designed SWGCs have competitive coupling efficiency, as high as \&\#x2212;3.8\&\#x2009;\&\#x2009;dB for the fundamental TE mode, and state-of-the-art back reflections, as low as \&\#x2212;23\&\#x2009;\&\#x2009;dB.