Photothermoelectric and Photoelectric Contributions to Light Detection in Metal–Graphene–Metal Photodetectors

Graphene's high mobility and Fermi velocity, combined with its constant light absorption in the visible to far-infrared range, make it an ideal material to fabricate high-speed and ultrabroadband photodetectors.However, the precise mechanism of photodetection is still debated.Here, we report wavelength and polarization-dependent measurements of metal-graphene-metal photodetectors.This allows us to quantify and control the relative contributions of both photothermo-and photoelectric effects, both adding to the overall photoresponse.This paves the way for a more efficient photodetector design for ultrafast operating speeds.