Crossover from time-correlated single-electron tunneling to that of Cooper pairs

Abstract

We have studied charge transport in a one-dimensional chain of small Josephson junctions using a single-electron transistor. We observe a crossover from time-correlated tunneling of single electrons to that of Cooper pairs as a function of both magnetic field and current. At relatively high magnetic field, single-electron transport dominates and the tunneling frequency is given by f=I/e, where I is the current through the chain and e is the electron's charge. As the magnetic field is lowered, the frequency gradually shifts to f=I/2e for I>200 fA, indicating Cooper-pair transport. For the parameters of the measured sample, we expect the Cooper-pair transport to be incoherent.

arXiv comment5 pages, 4 figures; v2: minor changes, clarifications, additions

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Cited by in corpus (4)

• The parity effect in Josephson junction arrays
• Parity effect and single-electron injection for Josephson-junction chains deep in the insulating state
• Correlated transport through junction arrays in the small Josephson energy limit: incoherent Cooper-pairs and hot electrons
• Crossover From Cooper-Pair Hopping to Single-Electron Hopping in Pb${}_x$(TiO${}_2$)${}_{1-x}$ Granular Films