A SQUID gradiometer with trimmable additional positive feedback

被引：0
作者：
Takada, Y
Tsukada, K
Adachi, A
机构：
[1] Superconducting Sensor Laboratory, Chiba 270-13
来源：
SUPERCONDUCTOR SCIENCE & TECHNOLOGY | 1996年 / 9卷 / 4A期
关键词：
D O I：
10.1088/0953-2048/9/4A/031
中图分类号：
O59 [应用物理学];
学科分类号：
摘要：
A SQUID gradiometer with a glass package and trimmable additional positive feedback (APF) is developed to achieve a low equivalent flux noise over a wide range of bias current. The noise characteristics of a SQUID with APF are investigated by varying the APF gain and the bias current. We found the most suitable APF parameter to achieve low equivalent flux noise over a wide range of bias current. When a SQUID with APF has a cc-planar first-order coil whose effective area is 100 mm(2), a typical gradiometer noise level of 7.4 fT Hz(-1/2) at 100 Hz and 21 fT Hz(-1/2) at 1 Hz is achieved.
引用
收藏
页码：A120 / A123
页数：4
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