On-chip matching networks for radio-frequency single-electron transistors

In this letter, the authors describe operation of a radio-frequency superconducting single electron transistor (rf-SSET) with an on-chip superconducting LC matching network consisting of a spiral inductor L and its capacitance to ground Cp. The superconducting network has a lower Cp and gives a better matching for the rf-SSET than does a commercial chip inductor. Moreover, the superconducting network has negligibly low dissipation, leading to sensitive response to changes in the rf-SSET impedance. The charge sensitivity δq=2.4×10−6e∕Hz in the subgap region and energy sensitivity δε=1.9ℏ indicate that the rf-SSET is operating in the vicinity of the shot noise limit.