Yba_2Cu_3O_7 dc SQUID magnetometers in various configurations have been fabricated using step-edge Josephson junctions, e.g. single-layer magnetometers as well as multilevel devices with an integrated flux transformer. We report on their noise characteristics: all devices exhibit intrinsic 1/f-noise originating only from critical current fluctuations. The fluctuation strength is typicallyδI_0/I_0 ≈ 10~(-4)/ √Hz. At 77K, the 1/f-noise is always suppressed using the flux-locked-loop readout scheme with ac-bias.
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