Anomalous magnetoresistance oscillations and enhanced superconductivity in single-crystal Pb nanobelts

Using atomically flat single-crystal Pb ultrathin films grown on Si(111) substrate by molecular beam epitaxy, we fabricated Pb nanobelts of 28 atomic monolayers thick, $285nm$ wide, and $10μm$ long by focus ion beam technique. The transport property is measured and the results are compared to the Pb films. We find that below the superconducting transition temperature $TC$⁠, the resistance of the nanobelts exhibits clear and reproducible oscillations as a function of perpendicular magnetic field, which are not observed in the Pb films. In addition, $TC$ enhancement was also observed in the nanobelts. The results suggest that the single-crystal Pb nanobelts prepared on Si semiconductor substrate offer a great opportunity for integrating superconducting circuits in a single Si chip.