High?Frequency Light Rectification by Nanoscale Plasmonic Conical Antenna in Point?Contact?Insulator?Metal Architecture

Numerous efforts have been undertaken to develop rectifying antennas operating at high frequencies, especially dedicated light harvesting and photodetection applications. However, the development of efficient frequency has a major technological challenge both due lack comprehension underlying physics limitations in fabrication techniques. Various rectification strategies implemented, including metal-insulator-metal traveling-wave diodes, plasmonic nanogap optical antennas, whisker although all show limited high-frequency operation modest conversion efficiencies. Here new type antenna based on carrier generation is demonstrated. The proposed structure consists resonant metallic conical nano-antenna tip contact with oxide surface an oxide/metal bilayer. shape allows for improved current plasmon-mediated electromagnetic-to-electron conversion, effect exploiting nanoscale-tip antenna, proportional resonance surface-electron scattering. Importantly, this solution provides 280 THz (1064 nm) 100-fold increase efficiency compared previously reported results. Finally, also demonstrated operate 384 (780 nm), hence paving way toward rectennas visible range.