中国物理B ›› 2022, Vol. 31 ›› Issue (2): 28504-028504.doi: 10.1088/1674-1056/ac2b91
Wentao Wu(伍文涛)1,2,†, Zhirong Lin(林志荣)1,2,3, Zhi Ni(倪志)1,2,3, Peizhan Li(李佩展)4,5, Tiantian Liang(梁恬恬)1,2,3, Guofeng Zhang(张国峰)1,2, Yongliang Wang(王永良)1,2, Liliang Ying(应利良)1,2, Wei Peng(彭炜)1,2,3, Wen Zhang(张文)4, Shengcai Shi(史生才)4, Lixing You(尤立星)1,2,3, and Zhen Wang(王镇)1,2,3
Wentao Wu(伍文涛)1,2,†, Zhirong Lin(林志荣)1,2,3, Zhi Ni(倪志)1,2,3, Peizhan Li(李佩展)4,5, Tiantian Liang(梁恬恬)1,2,3, Guofeng Zhang(张国峰)1,2, Yongliang Wang(王永良)1,2, Liliang Ying(应利良)1,2, Wei Peng(彭炜)1,2,3, Wen Zhang(张文)4, Shengcai Shi(史生才)4, Lixing You(尤立星)1,2,3, and Zhen Wang(王镇)1,2,3
摘要: A cold preamplifier based on superconducting quantum interference devices (SQUIDs) is currently the preferred readout technology for the low-noise transition edge sensor (TES). In this work, we have designed and fabricated a series SQUID array (SSA) amplifier for the TES detector readout circuit. In this SSA amplifier, each SQUID cell is composed of a first-order gradiometer formed using two equally large square washers, and an on-chip low pass filter (LPF) as a radio-frequency (RF) choke has been developed to reduce the Josephson oscillation interference between individual SQUID cells. In addition, a highly symmetric layout has been designed carefully to provide a fully consistent embedded electromagnetic environment and achieve coherent flux operation. The measured results show smooth V-Φ characteristics and a swing voltage that increases linearly with increasing SQUID cell number N. A white flux noise level as low as 0.28 μΦ0/Hz1/2 is achieved at 0.1 K, corresponding to a low current noise level of 7 pA/Hz1/2. We analyze the measured noise contribution at mK-scale temperatures and find that the dominant noise derives from a combination of the SSA intrinsic noise and the equivalent current noise of the room temperature electronics.
中图分类号: (Superconducting quantum interference devices (SQUIDs))