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A Compact High-Tc RF-SQUID System with Reduced Tank Circuit Damping

  • Yi Zhang
  • C. Heiden
Part of the Springer Proceedings in Physics book series (SPPHY, volume 64)

Abstract

One requirement for good rf-SQUID operation is a coupling between SQUID-ring and tank circuit with k2Q≈1. For typical bulk SQUID structures of high-Tc materials, however k2Q<1 usually is found experimentally, when using a copper coil at 77 K for the tank circuit and a resonance frequency near 20 MHz. We therefore investigated the operation of high-Tc rf-SQUIDs where the damping of the tank circuit was reduced by a positive feedback circuit in order to achieve k2Q≥1. The reduction of damping leads to noise reduction. The SQUID can be operated without external rf-oscillator solely driven by the tank circuit noise. This elimination of the oscillator leads to a simplified compact “SQUID-STICK”.

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References

  1. [1]
    Yi Zhang, Yunhui Xu, and C. Heiden, Appl. Phys. Lett. 56, 1579 (1990).ADSCrossRefGoogle Scholar
  2. [2]
    G. Cui, Y. Zhang, K. Hermann, C. Buchal, J. Schubert, A.I. Braginski, and C. Heiden, Supercon. Sei. and Tech. 4, S130 (1991).Google Scholar
  3. [3]
    C.L. Jia, B. Kabius, K. Urban, K. Herrmami, G.J. Cui, J. Schubert, W. Zander, A.I. Braginski, and C. Heiden, Physica C 175, 545 (1991).Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • Yi Zhang
    • 1
  • C. Heiden
    • 1
  1. 1.Institut für Schicht und Ionentechnik (ISI)Forschungszentrum Jülich (KFA)JülichFed. Rep. of Germany

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