A NbN-based programmable Josephson voltage standard arrays (PJVAs) have been investigated. We show that these arrays can be utilized for programmable operation up to /spl plusmn/1 V. The results of direct comparisons between the PJVA and a conventional superconductor-insulator-superconductor Josephson array agree at voltages between 0.1 V and 1 V within an uncertainty of better than 1 nV. An indirect comparison via a Zener voltage reference also shows agreement within a 1/spl sigma/ type A uncertainty of 13 nV.
['Chiharu Urano', 'Yasushi Murayama', 'Akio Iwasa', 'Akira Shoji', 'Hirotake Yamamori', 'Mayumi Ishizaki']
A precise evaluation of NbN-based 1-V programmable Josephson voltage standard arrays