Title :
Seven-channel RF SQUID with 1/f noises only at very low frequencies
Author :
Ohta, Hiroshi ; Takahata, Mitsuhiro ; Takahashi, Yoshiaki ; Shinada, Kei ; Yamada, Yasuharu ; Hanasaka, Takao ; Uchikawa, Yoshinori ; Kotani, Makoto ; Matsui, Toshiaki ; Komiyama, Bokiji
Author_Institution :
Inst. of Phys. & Chem. Res., Wako-shi, Saitama, Japan
fDate :
3/1/1989 12:00:00 AM
Abstract :
A seven-channel RF SQUID (superconducting quantum interference device) with anodized short weak links has been fabricated. The devices exhibit a sensitivity of 23.6 fT/√Hz and a 1/f noise onset of 0.05 Hz at a white noise level of 1.8×10-4 φ0/√Hz. The intrinsic flux noise is estimated from an observed step pattern to be 4.9×10-5 φ0 /√Hz. It is shown that Arnold theory explains very well the behavior of Josephson junctions with a critical current density of around 104 A/cm2
Keywords :
SQUIDs; electron device noise; 1/f noises; Arnold theory; Josephson junctions; anodized short weak links; critical current density; intrinsic flux noise; seven-channel RF SQUID; step pattern; very low frequencies; white noise level; Critical current; Low-frequency noise; Magnetic noise; Niobium; Quadratic programming; Radio frequency; SQUIDs; Sputtering; Substrates; Transistors;
Journal_Title :
Magnetics, IEEE Transactions on
