We report the observation of an apparent metallic state induced by a parallel magnetic field in Au 0.7In 0.3 samples with very low normal-state sheet resistance. These samples can be modeled as a random array of superconductor-normal metal-superconductor (SNS) junctions. For both the thin planar and cylindrical films, the magnetic field was applied parallel to the substrate of the sample and measurement currents. For the mesoscopic rings, however, a perpendicular field was used. Our electrical transport and tunneling measurements suggest that the samples consist of superconducting In-rich islands not linked by Josephson coupling in the metallic state. The physical origin of the metallic state is discussed.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
- Materials Science(all)
- Condensed Matter Physics