Resonant tunneling through a macroscopic charge state in a superconducting SET transistor
نویسندگان
چکیده
We predict theoretically and observe in experiment that the differential conductance of a superconducting SET transistor exhibits a peak which is a complete analogue in a macroscopic system of a standard resonant tunneling peak associated with tunneling through a single quantum state. In particular, in a symmetric transistor, the peak height is universal and equal to e/2πh̄. Away from the resonance we clearly observe the co-tunneling current which in contrast to the normal-metal transistor varies linearly with the bias voltage. PACS numbers: 73.40.Gk, 74.50.+r Typeset using REVTEX
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