Double-bonded InP-InGaAsP vertical coupler 1:8 beam splitter

A novel three-layer double-bonded InP-InGaAsP waveguide vertical coupler 1:8 beam splitter is demonstrated. The strongly coupled waveguides allow a 583-μm device length, more than 100 times shorter than that of the equivalent horizontal coupler. The device illustrates the use of multiple vertical-layer optical interconnects for three-dimensional routing of optical signals.