Surface plasmon assisted hot electron collection in wafer-scale metallic-semiconductor photonic crystals.

Plasmon assisted photoelectric hot electron collection in a metal-semiconductor junction can allow for sub-bandgap optical to electrical energy conversion. Here we report hot electron collection by wafer-scale Au/TiO metallic-semiconductor photonic crystals (MSPhC), with a broadband photoresponse below the bandgap of TiO. Multiple absorption modes supported by the 2D nano-cavity structure of the MSPhC extend the photon-metal interaction time and fulfill a broadband light absorption.