| 摘要 |
The present invention comprises a high-transition-temperature superconducting device having low-magnitude low-frequency noise-characteristics in magnetic fields comprising superconducting films wherein the films have a width that is less than or equal to a critical width, wC, which depends on an ambient magnetic field. For operation in the Earth's magnetic field, the critical width is about 6 micrometers ( mu m). When made with film widths of about 4 mu m an inventive high transition-temperature, superconducting quantum interference device (SQUID) excluded magnetic flux vortices up to a threshold ambient magnetic field of about 100 microTesla ( mu T). SQUIDs were fabricated having several different film strip patterns. When the film strip width was kept at about 4 mu m, the SQUIDs exhibited essentially no increase in low-frequency noise, even when cooled in static magnetic fields of magnitude up to 100 mu T. Furthermore, the mutual inductance between the inventive devices and a seven-turn spiral coil was at least 85% of that for inductive coupling to a conventional SQUID.
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