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We propose a mesoscopic kinetic-inductance radiation detector based on a long superconductor--normal metal--superconductor Josephson junction. The operation of this proximity Josephson sensor (PJS) relies on large kinetic inductance variations under irradiation due to the exponential temperature dependence of the critical current. Coupled with a dc SQUID readout, the PJS is able to provide a signal to noise (S/N) ratio up to ~10^3 in the THz regime if operated as calorimeter, while electrical noise equivalent power (NEP) as low as ~7x10^{-20} W(Hz)^(-1/2) at 200 mK can be achieved in the bolometer operation. The high performance together with the ease of fabrication make this structure attractive as an ultrasensitive cryogenic detector of THz electromagnetic radiation., 4 pages, 3 figures

Power generation and synchronization in Josephson junction arrays have attracted attention for a long time stemming both from fundamental interest and from application potential. The authors study the array of junctions coupled to a distributed transmission line either driven by an external microwave signal or in a self-oscillating mode. The authors simplify the theoretical treatment in terms of harmonic analysis and power balance. The model explains large operation margins of superconductor-normal-superconductor and superconductor-insulator-normal-insulator-superconductor junction arrays. The authors also compare theory, experiments, and simulations of self-oscillating externally shunted superconductor-insulator-superconductor junction arrays.