a) Schematic illustration of the optical characterization setup. The red cone illustrates the beam emitted from the PIC. b) Cutback measurement to deduce the coupling and propagation losses for the TE and TM modes at a wavelength of 760 nm. Data points shown with reduced opacity were excluded from the fit. c) Characterization of the EBL–OL transition taper, showing the extracted taper loss. The inset displays the cascaded taper section.