Title :
Noise properties of SQUIDs with step-edge Josephson junctions
Author :
Glyantsev, V.N. ; Siegel, M. ; Schubert, J. ; Zander, W. ; Poppe, Ulrich ; Soltner, H. ; Braginski, A.I. ; Heiden, C.
Author_Institution :
Inst. fur Schicht- und Ionentechnik, Forschungszentrum Julich, Germany
fDate :
3/1/1993 12:00:00 AM
Abstract :
The authors investigated low-frequency noise in RF and DC superconducting quantum interference devices (SQUIDs) with step-edge Josephson junctions (SEJs). The noise properties have been measured as a function of frequency, temperature, bias current, and magnetic field. The low-frequency noise has a telegraph-like character in certain conditions and depends quasi-periodically on flux and temperature. This telegraph noise was also observed in single step-edge junctions. The experimental results were explained by a model of such a junction in which an array of parallel and series connected weak links acts like a two-level fluctuator. This fluctuator arises from the quantum states of a multijunction SQUID with spatially inhomogeneous SEJs resembling a multijunction array.<>
Keywords :
Josephson effect; SQUIDs; electron device noise; DC type; RF type; SQUIDs; bias current; low-frequency noise; magnetic field; model; noise properties; step-edge Josephson junctions; superconducting quantum interference devices; telegraph-like character; temperature; two-level fluctuator; weak links; Josephson junctions; Low-frequency noise; Magnetic field measurement; Magnetic noise; Magnetic properties; Radio frequency; Radiofrequency interference; SQUIDs; Superconducting device noise; Superconducting devices;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
