一种抑制市电对高温SQUID干扰的新方法

A new method for suppressing the power-line interference in high T_C SQUIDS

提出了一种抑制市电对高温SQUID磁强计干扰的电源平衡方案 ,并且用在无屏蔽环境中的实验证实了它的可行性 .与高阶梯度计方案相比 ,虽然当环境干扰改变时 ,它保持平衡的能力较低 ,但是这种方法不仅简单易行 ,而且对SQUID不引入任何附加的本征噪声 ,从而可大大降低建造昂贵电磁屏蔽室的费用 .

In this paper, we propose a new method with power supply source balanced for suppressing the power-line interference in high-T c SQUIDs. Its feasibility is tested and verified by experiments in an unshielded environment. In comparison with the scheme of high-order SQUID gradiometer, the method is simple without introducing any extra-intrinsic noise to SQUID sensor. In addition, the high cost in constructing electromagnetically shielded room can be greatly reduced. However, its capability in keeping the balance is worse than high-order gradiometer if external interference change occurs.