Some remarks about the flux periodicity in SQUIDS
A topolotical approach is used to show that the flux periodicity of any practical single-junction rf SQUID or double-junction dc SQUID device is one flux quantum (Phi/sub 0/). The flux periodicity is independent of the number of superconducting loops and circuit inductances. The topological point of view explains how multihole configurations can be derived from a toroidal one. Weak links are considered as topological switches that allow magnetic flux lines to pass from one homotopic class of loops to another. In addition to rf SQUIDs in the hysteretic or nonhysteretic regime, we also consider resistive and dc SQUIDs. Some special caes are also introduced where the flux periodicity is not Phi/sub 0/, due to special nonlinear behavior of the weak link, due to coupling to a resonant circuit, or because of a great number of weak links in the superconducting circuit. The flux periodicity of a SQUID is a property of the weak link itself, and not of the inductances connected to it. Only the number of weak links and their mutual connection in series or parallel can change the fundamental flux periodicity of the device.
- Research Organization:
- Institute of Physics, Czechoslovak Academy of Sciences, Rez, Czechoslovakia
- OSTI ID:
- 6220472
- Journal Information:
- J. Low Temp. Phys.; (United States), Vol. 57:3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Some remarks on the theory of SQUID structures. I. Topology of SQUID structures: A unified picture
A Numerical Treatment of the Rf SQUID: I. General Properties andNoise Energy
Related Subjects
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
SQUID DEVICES
MAGNETIC FLUX
HYSTERESIS
JOSEPHSON EFFECT
NONLINEAR PROBLEMS
SUPERCONDUCTING JUNCTIONS
TOPOLOGY
VARIATIONS
ELECTRONIC EQUIPMENT
EQUIPMENT
FLUXMETERS
JUNCTIONS
MATHEMATICS
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
SUPERCONDUCTING DEVICES
420201* - Engineering- Cryogenic Equipment & Devices
656102 - Solid State Physics- Superconductivity- Acoustic
Electronic
Magnetic
Optical
& Thermal Phenomena- (-1987)