We report the applicability of YBa 2Cu 3O 7-y (YBCO) SQUIDs fabricated by field-emission electron beam source. The junctions show hysteresis and self-resonance steps related to a high frequency resonance in the dc SQUID loop at a voltage V res = φ 2 / 2π(LC / 2) 1/2 around 0.3 T c. The noise spectrum of the SQUIDs was measured with de-bias schemes at different temperatures and showed values around 10 -4 φ 0/Hz 1/2 down to frequencies of 10 Hz at 40 K. The influence of magnetic flux, operating temperatures and flux-voltage transfer factor (|dV/d<SJ ) were investigated. We also tested inverter operation of a de-biased Josephson logic gate composed of an rf SQUID and a dc SQUID to realize logic circuit performance. Operation of the inverter has been successfully demonstrated although the operating temperature is low, around 10 K.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering