title: Photodetection with active optical antennas.
abstract: Nanoantennas are key optical components for light harvesting; photodiodes convert light into a current of electrons for photodetection. We show that these two distinct, independent functions can be combined into the same structure. Photons coupled into a metallic nanoantenna excite resonant plasmons, which decay into energetic, "hot" electrons injected over a potential barrier at the nanoantenna-semiconductor interface, resulting in a photocurrent. This dual-function structure is a highly compact, wavelength-resonant, and polarization-specific light detector, with a spectral response extending to energies well below the semiconductor band edge.
authors.affiliation: Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005, USA.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Knight
authors.forename: Heidar
authors.initials: H
authors.lastname: Sobhani
authors.forename: Peter
authors.initials: P
authors.lastname: Nordlander
authors.forename: Naomi J
authors.initials: NJ
authors.lastname: Halas