Improved 10 V josephson voltage standard arrays

摘要

10V Josephson voltage standard arrays are fabricated with an Nb/Al_2O_3/Nb trilayer deposited directly on the Si wafer. The edges of the base electrode are insulated by a modified anodization process. A microstrip network without dc blocks is newly designed, using a double finline taper. The width of the constant-voltage steps monotonically decreases with the microwave power for good arrays. Switching between different voltage levels from 10 V to 0 V and vice versa is possible by simply switching the dc voltage bias without rf-power adjustment.