A 0.2-0.5 THz 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 0.2-0.5 THz. In the bandwidth of 74% of the center frequency, this single-band receiver exhibits noise temperature of T(RX)<= 20hf/k(B), where h is Planck's constant, f is the frequency, and k(B) is Boltzmann's constant. Resultant T(RX) is almost equal to T(RX) of the identical SIS mixer pumped by three conventional frequency-multiplier-based LOs which share the 0.2-0.5 THz band. This technique will contribute to simple, wide-band, and low-noise heterodyne receivers in the terahertz region. (c) 2008 American Institute of Physics.