We describe the noise performance of dc SQUIDs fabricated with quasiplanar ramp-type Josephson junctions on the basis of c-axis-oriented YBa2Cu3O7 /PrBa2Cu3O7 thin-film heterostructures. The noise spectrum of the dc SQUIDs was measured with dcand ac-bias schemes at different temperatures and showed values below 10 F0 /Hz 1/2 down to frequencies of about 1 Hz at 70 K. Up to now for the magnetic ...
