Development of a compact Josephson voltage standard based on NbN/TiN/NbN array operating at 12K

A compact Programmable Josephson Voltage Standard (PJVS) system based on a cryocooler is under development at the National Institute of Advanced Industrial Science and Technology (AIST). The system uses a 2 V NbN/TiN/NbN PJVS chip operating at 12 K. Since the PJVS chip requires cooling power of less than 100 mW, it is possible to use a compact-size cryocooler, which may be mounted inside a standard 19-inch rack-mount chassis. By combining the 2 V PJVS chip with a high-precision semiconductor voltage multiplier circuit, it is possible to generate arbitrary voltages up to 20 V.