High-Speed Antenna-Coupled Terahertz Thermocouple Detectors and Mixers

An antenna-coupled nanothermocouple (ACNTC) is an integrated structure consisting of a dipole nanoantenna and a nanothermocouple (NTC). ACNTCs are excellently suited as polarization-sensitive detectors and mixers for the long-wavelength far-infrared range around 30 THz. Radiation collected by the integrated nanoantenna and fed into the hot junction creates a temperature difference between the hot and cold junctions of the thermocouple, which results in open-circuit voltage due to the Seebeck effect. Due to the geometry-dependence of the Seebeck coefficient in nanowires, we realize single-metal ACNTCs. The fundamentals of single-metal NTCs are discussed. The thermal dynamics of NTCs is investigated showing that NTCs could exhibit mixer and detector intermediate frequency and low frequency cutoffs beyond 100 GHz. We provide experimental evidence of ACNTCs.