Energy gap measurement of nanostructured thin aluminium films for use in single Cooper-pair devices

Abstract

Within the context of superconducting gap engineering, Al-\alox-Al tunnel junctions have been used to study the variation in superconducting gap, $\Delta$, with film thickness. Films of thickness 5, 7, 10 and 30 nm were used to form the small area superconductor-insulator-superconductor (SIS) tunnel junctions. In agreement with previous measurements we have observed an increase in the superconducting energy gap of aluminium with a decrease in film thickness. In addition, we find grain size in small area films with thickness \textbf{$\ge$} 10 nm has no appreciable effect on energy gap. Finally, we utilize 7 and 30 nm films in a single Cooper-pair transistor, and observe the modification of the finite bias transport processes due to the engineered gap profile.

References in corpus (4)

• Microsecond resolution of quasiparticle tunneling in the single-Cooper-pair-transistor
• Time-domain measurements of quasiparticle tunneling rates in a single-Cooper-pair transistor
• Parity effect in superconducting aluminum single electron transistors with spatial gap profile controlled by film thickness
• Spin-Dependent Quasiparticle Transport in Aluminum Single Electron Transistors

Cited by in corpus (1)

• A quantitative study of quasiparticle traps using the single-Cooper-pair-transistor