A 0.2–0.5THz single-band heterodyne receiver based on a photonic local oscillator and a superconductor-insulator-superconductor mixer

We have demonstrated that a superconductor-insulator-superconductor (SIS) mixer pumped by a photonic local oscillator (LO) covers the whole frequency range of 0.2–0.5THz. In the bandwidth of 74% of the center frequency, this single-band receiver exhibits noise temperature of TRX⩽20hf∕kB, where h is Planck’s constant, f is the frequency, and kB is Boltzmann’s constant. Resultant TRX is almost equal to TRX of the identical SIS mixer pumped by three conventional frequency-multiplier-based LOs which share the 0.2–0.5THz band. This technique will contribute to simple, wide-band, and low-noise heterodyne receivers in the terahertz region.