Arrays of "nanorectennas" consist of diode-coupled nanoantennas with plasmonic resonances in the visible/near-infrared
(vis/nir) regime, and are expected to convert vis/nir radiative power into useful direct current. We study plasmonic
resonances in large format (~ 1 mm2 area) arrays, consisting of electron beam-patterned horizontal (e.g., parallel to the substrate) Ag lines patterned on ultrathin (< 20 nm) tunneling barriers (NiO, NbOx, and other oxides). Our e-beam fabrication technique is scalable to large dimensions, and allows us to easily probe different antenna dimensions. These
tunneling barriers, located on a metallic ground plane, rectify the alternating current generated in the nanoantenna at
resonance. We measure the plasmonic resonances in these nanoantennas, and find good agreement with modeling,
which also predicts that the electric field driving the electrons into the ground plane (and therefore the rectification
efficiency) is considerably enhanced at resonance. Various metal-insulator-metal tunneling diodes, incorporating the
afore-mentioned barrier layers and different metals for the ground plane, are experimentally characterized and compared
to our conduction model. We observe ~ 1 mV signals from NiO-based nanorectenna arrays illuminated by 532 nm and
1064 nm laser pulses, and discuss the origin of these signals.
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