Graphene-based THz photodetector by noise-thermometric technique

Terahertz (THz) photo-detectors, consisting of a r graphene nano-bridge and a plane antenna have been fabricated c and characterized. Hot electrons in graphene-bridge (GB) are generated after absorbing the incident THz photons. We measured the amplified thermal noise power from hot electrons to sense the absorbed THz power. By using this noise-thermometric technique, a THz photodetector with temperature responsivity of 5 K/nW has been achieved. We also demonstrated that the heat relaxation of nano-GB is dominated by electron diffusion process.