Nb/Al-AlOx/Nb overdamped junctions suitable for voltage standard operation above 4.2 K

Author

Lacquaniti, Vincenzo ; Leo, Natascia De ; Fretto, Matteo ; Sosso, Andrea

Author_Institution

Ist. Naz. di Ricerca Metrologica, Torino

fYear

2008

fDate

8-13 June 2008

Firstpage

106

Lastpage

107

Abstract

Nb/Al-AlOx/Nb Josephson junctions of few micrometers size, derived by the basic hysteretic SIS process, have shown stable overdamped current voltage, I-V, characteristic with Ic of 1-10 mA and Vc of 100-600 muV at 4.2 K. The moderate dependence on temperature of these parameters has allowed to use them at temperatures above 4.2 K, near the Nb transition temperature, measuring quantized voltage steps several hundreds muA wide on single and 10 junctions arrays at T > 8 K. This paves the way to their use in cryocooler setup of reduced cost and power consumption for a future generation of programmable and AC voltage standard.

Keywords

aluminium; measurement standards; niobium; superconducting arrays; superconducting junction devices; voltage measurement; AC voltage standard; Josephson junctions; Nb-Al-AlO_x-Nb; cryocooler setup; current 1 mA to 10 mA; hysteretic SIS process; junctions arrays; overdamped current-voltage characteristics; overdamped junctions; temperature 4.2 K; voltage 100 muV to 600 muV; Current measurement; Hysteresis; Josephson junctions; Measurement standards; Niobium; Power measurement; Size measurement; Temperature dependence; Virtual colonoscopy; Voltage measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Precision Electromagnetic Measurements Digest, 2008. CPEM 2008. Conference on

Conference_Location

Broomfield, CO

Print_ISBN

978-1-4244-2399-6

Electronic_ISBN

978-1-4244-2400-9

Type

conf

DOI

10.1109/CPEM.2008.4574675

Filename

4574675