Voltage versus flux relation of dc superconducting quantum interference device using three josephson junctions

Keiji Enpuku, Hideki Doi

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

It has been shown that the voltage versus flux (V-Φ) relation of dc superconducting quantum interference devices (SQUIDs) operating at T=77 K is degraded considerably by thermal noise. Since degradation of modulation voltage in the V-Φ relation becomes more significant when inductance increases, a very restricted range of inductance exists which can be used at T=77 K. In order to reduce the degradation due to thermal noise and to enable the use of large inductances, a new SQUID using three Josephson junctions (3J-SQUID) is proposed. Numerical simulation shows that inductance of 3J-SQUID can be increased to twice as large as that of the conventional case without degrading modulation voltage. It is also shown that modulation voltage is highly improved by damping resistance parallel to inductance. As a result, we can expect to use inductances as large as L <500 pH if 3J-SQUID with damping resistance is employed. Large inductances available in 3J-SQUID will be useful in realizing efficient coupling of external magnetic field to the SQUID inductance.

Original languageEnglish
Pages (from-to)1856-1862
Number of pages7
JournalJapanese Journal of Applied Physics
Volume33
Issue number4R
DOIs
Publication statusPublished - 1994

Fingerprint

SQUIDs
inductance
Inductance
Josephson junctions
Fluxes
interference
Electric potential
electric potential
Thermal noise
thermal noise
Modulation
modulation
Damping
damping
degradation
Degradation
Magnetic fields
Computer simulation
magnetic fields

All Science Journal Classification (ASJC) codes

  • Engineering(all)
  • Physics and Astronomy(all)
  • Physics and Astronomy (miscellaneous)

Cite this

Voltage versus flux relation of dc superconducting quantum interference device using three josephson junctions. / Enpuku, Keiji; Doi, Hideki.

In: Japanese Journal of Applied Physics, Vol. 33, No. 4R, 1994, p. 1856-1862.

Research output: Contribution to journalArticle

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