A fast open-cycle cryocooler for cryogenic high-speed signal processing circuits

The design of a liquid helium based open-cycle cryocooler for small scale integrated Josephson junction circuits is described. In addition to low, medium and high speed transmission line access to the circuits, the cooler features a rapid startup time and low liquid consumption. The system makes use of materials and circuits manufactured on substrates with low thermal conductivity cooled by counterflow heat exchange between the working medium and the influx of heat.