We propose a design for two-dimensional arrays of stacked Josephson junctions and study their properties as coherent sources of radiation in the mm and sub-mm wavelength range. This design can be implemented by using either mesas of intrinsic Josephson junctions, from crystals of high TC superconductors, or artificial stacks of low TC junctions. We outline a possible Nb/AlOx/Nb trilayer fabrication process for such devices. Our model for the dynamics of the system predicts the range of parameters over which the junctions synchronize.
High-Tc superconducting (HTS) receivers are promising candidates for terahertz (THz) communication applications due to their superior sensitivity and the cooling attainability with a miniature cryogenic system. Nevertheless, currently reported HTS mixers are mostly single-junction devices, and a more complicated architecture like the balanced configuration has not been investigated. This paper presents the design of a 600-GHz single-balanced HTS mixer, where detailed electromagnetic simulations are carried out to optimize the coupling efficiency and port isolation, as well as desired amplitude and phase relationship. To predict the noise and conversion performance, we present an innovative multiport network interleaving-based modeling method that enables powerful simulation verifications for single-balanced HTS Josephson mixers. Simulation results show that the presented device exhibits very good HTS mixer performance at the 600-GHz band, which validates the effectiveness of the design and the potential of the mixer for THz communication applications.