2003/12/31 by Michio Watanabe
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Surface and Thin Film Phenomena #cond-mat.dis-nn #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.69.094509
published as Phys. Rev. B 69, 094509 (2004) · 8 pages with 10 embedded figures, RevTeX4, published version
arxiv created 2004/03/12 · openalex publication_date 2004/03/12 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The current--voltage (I--V) characteristics of single-electron transistors (SETs) have been measured in various electromagnetic environments. Some SETs were biased with one-dimensional arrays of dc superconducting quantum interference devices (SQUIDs). The purpose was to provide the SETs with a magnetic-field-tunable environment in the superconducting state, and a high-impedance environment in the normal state. The comparison of SETs with SQUID arrays and those without arrays in the normal state confirmed that the effective charging energy of SETs in the normal state becomes larger in the high-impedance environment, as expected theoretically. In SETs with SQUID arrays in the superconducting state, as the zero-bias resistance of the SQUID arrays was increased to be much larger than the quantum resistance RK\ensuremath≡h/e2\ensuremath≈26k\ensuremathΩ, a sharp Coulomb blockade was induced, and the current modulation by the gate-induced charge was changed from e periodic to 2e periodic at a bias point 0<|V|<2\ensuremathΔ0/e, where \ensuremathΔ0 is the superconducting energy gap. The author discusses the Coulomb blockade and its dependence on the gate-induced charge in terms of the single Josephson junction with gate-tunable junction capacitance.