Title :
Programmable Josephson Arrays for Impedance Measurements
Author :
Lee, Jinni ; Schurr, Jürgen ; Nissilä, Jaani ; Palafox, Luis ; Behr, Ralf ; Kibble, Bryan P.
Author_Institution :
Phys.-Tech. Bundesanstalt, Braunschweig, Germany
fDate :
7/1/2011 12:00:00 AM
Abstract :
Arbitrary impedance ratios can be determined with high accuracy by means of a programmable Josephson system. For a 1 : 1 resistance ratio at 10-kΩ level, we demonstrate that the novel system allows measurements over a wide frequency range from 25 Hz to 6 kHz. Uncertainties are in the range of a few parts in 108 and thus comparable to those of conventional impedance bridges. Two methods for four-terminal-pair impedance measurements have been investigated, i.e., the potential comparison circuit and the coaxial setup. Both methods are capable of measuring from dc to 6 kHz with uncertainties to a few parts in 108. The potential comparison circuit has an upper bound at 6 kHz due to the use of the sampling method. The four-terminal-pair coaxial setup has the potential to decrease the relative uncertainty down to 10-9 once systematic errors are analyzed and canceled.
Keywords :
Josephson effect; electric impedance measurement; measurement uncertainty; superconducting junction devices; arbitrary impedance ratio; four-terminal-pair coaxial setup; four-terminal-pair impedance measurements; frequency 25 Hz to 6 kHz; impedance bridges; measurement uncertainty are; potential comparison circuit; programmable Josephson arrays; relative uncertainty; resistance 10 kohm; resistance ratio; Bridge circuits; Electrical resistance measurement; Frequency measurement; Impedance; Impedance measurement; Resistors; Voltage measurement; Impedance bridge; Josephson array; impedance measurement; signal synthesis;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
DOI :
10.1109/TIM.2011.2117311