Superconductor Science and Technology

Multiturn flux transformers for rf SQUID magnetometers

H R Yi, Jürgen Schubert, W. Zander, Xian-Lin Zeng, M. Banzet, Dongfeng He, Y Zhang

Published Jul 1, 1998• 3 citations

Abstract

This work showed experimentally how the planar multiturn input coil of a flux transformer could be integrated with a coplanar resonator while still permitting one to couple radio frequency (rf) signals to an rf SQUID. A new layout of a multiturn flux transformer with one pickup loop and two input coils, one single turn and one multiturn, has been fabricated on (001) substrates and evaluated. A planar double-hole washer SQUID was inductively coupled to the two separate input coils via a flip chip configuration. With this layout the best magnetometer showed magnetic field white noise of at 77 K in a magnetically shielded surrounding.

DOI: 10.1088/0953-2048/11/7/013

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