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GaAs-based gain waveguides with U-bend architecture enabling low loss and high yield hybrid integration on silicon photonic circuits

Research output: Other conference contributionPaper, poster or abstractScientific


Original languageEnglish
Publication statusPublished - 2019
Publication typeNot Eligible
EventEuropean conference on integrated optics 2019 - Ghent University, Ghent, Belgium
Duration: 24 Apr 201926 Apr 2019
Conference number: 21


ConferenceEuropean conference on integrated optics 2019
Abbreviated titleECIO 2019


We present a U-bend design for traveling wave III-V gain devices, such as semiconductor optical amplifiers and laser diodes. The design greatly simplifies the butt-coupling between the III-V chip and silicon-on-insulator photonic circuit by bringing the I/O ports on one facet. This removes the need for precise dimension control otherwise required for 2-side coupling, therefore increasing the yield of mounted devices towards 100%. The design, fabrication and characterization of the U-bend device based on Euler bend geometry is presented. The losses for a bend with a minimum bending radius of 83 μm are 1.1 dB. In addition, we present an analysis comparing the yield and coupling losses of the traditionally cleaved devices with the results that the Euler bend approach enable, with the final conclusion that the yield is improved by several times while the losses are decreased by several dB.


  • Hybrid integration, III-V, Semiconductor optical amplifiers, Silicon-on-insulator, Coupling losses