Nanostructure antennas for the LW-IR regime

We review our previous work demonstrating planar dipole antenna structures which operate in the LW-IR regime (30 THz). Integrated metal-oxide-metal tunnel diodes are used as the rectifying element. These nanoantenna structures exhibit a polarization and length dependence expected from classical dipole antennas. We measure specific detectivities of 2*10⁶ cmHz^1/2W^-1. One way of increasing the detectivity of these antenna structures, which currently are fabricated on top of a silicon-silicon dioxide structure, is to place them on top of a cavity filled with a low-k dielectric to achieve higher antenna gain. We have explored the performance of cavity-backed dipoles for LW-IR operation by numerical simulations, and have experimentally verified the performance of these structures with a 1000-x scale model operating in Ka-band (30 GHz).