“…The QWI process could in-duce large blue-shift but will also introduce damages to material while ion implantation is carried out. [5,6] In contrast, as a simpler mutation from butt-joint, bundle integrated waveguide (BIG) takes the advantage of large blue-shift, low loss, small vertical divergence angle, simplicity of fabrication and so appears to be an elegant monolithic integration solution, because BIG involves only one step selective removal of the active core in passive region, which is followed by a non-selective epitaxial growth all over the wafer with relatively good butt-joint interface. [7] Fig.…”