  Superconducting nanowire single photon detectors are rapidly emerging as a
key infrared photon-counting technology. Two front-side-coupled silver dipole
nanoantennas, simulated to have resonances at 1480 nm and 1525 nm, were
fabricated in a two-step process. An enhancement of 50% to 130% in the system
detection efficiency was observed when illuminating the antennas. This offers a
pathway to increasing absorption into superconducting nanowires, creating
larger active areas, and achieving more efficient detection at longer
wavelengths.
