Large RF-controlled voltage steps in DC SQUIDs applicable to voltage standards and sources

Author

Lee, G.S. ; Ho, H.L. ; Ruby, R.C. ; Barfknecht, A.T.

Author_Institution

Hewlett-Packard Lab., Palo Alto, CA, USA

Volume

3

Issue

1

fYear

1993

fDate

3/1/1993 12:00:00 AM

Firstpage

2740

Lastpage

2743

Abstract

The current height of RF-induced voltage steps in nonhysteretic single Josephson junctions is usually a small fraction of the critical current. It is demonstrated that when a resistively shunted DC superconducting quantum interference device (SQUID) is subjected to an RF magnetic flux, a voltage step with a large current height is obtained. In contrast to weak selection rules for single Josephson junctions, strong selection of the step harmonic number occurs in a shunted DC SQUID for appropriate choice of RF amplitude and DC flux offset, with odd harmonic numbers selected by half-integer flux quantum offsets and even harmonic numbers by integer flux quantum offsets. This pronounced effect has immediate implications for voltage standards and fast, high-precision digital-to-analog converters.<>

Keywords

Josephson effect; SQUIDs; measurement standards; reference circuits; DC SQUIDs; DC flux offset; RF amplitude; RF magnetic flux; RF-controlled voltage steps; critical current; flux quantum offsets; high precision ADCs; nonhysteretic single Josephson junctions; resistively shunted; superconducting quantum interference device; voltage sources; voltage standards; Critical current; Critical current density; Digital-analog conversion; Frequency; Josephson junctions; Laboratories; Magnetic flux; Millimeter wave technology; SQUIDs; Voltage;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.233514

Filename

233514