Heterodyne mixer using superconductor-normal metal-superconductor junction

We propose a design for a millimeter-wave-radio-astronomy heterodyne mixer using a superconductor-normal metal-superconductor junction device as the mixer. We simulate its current-voltage characteristics as a function of its relevant physical parameters, we use its non-linearity for mixing frequencies and its negative derivative to calculate the conversion gain. As the radiofrequency sensor is a SQUID, the whole system should be operated at low temperature, below the superconducting transition at Tc, avoiding any thermal interface.