Edge-illuminated refracting-facet photodiode withhigh responsivity and low-operation voltage

The authors propose a novel edge-illuminated refracting-facet photodiode (RFPD), where the incident light parallel to the up-side surface is refracted at an angled facet and absorbed in a thin absorption layer. Fabricated RFPDs with an absorption layer thickness of 1.5 µm show a responsivity as high as 0.96 A/W even at a bias voltage of 0.5 V for a flat-ended singlemode fibre.