Thermally-fluctuated single-flux-quantum pulse intervals reflected in input-output characteristics of a double-flux-quantum amplifier

29th International Symposium on Superconductivity

Mizugaki, Yoshinao^1 ; Urai, Yoshiaki^1 ; Shimada, Hiroshi^1

Department of Engineering Science, University of Electro-Communications (UEC Tokyo), Chofu, Tokyo

182-8585, Japan^1

关键词: Double-flux-quantum;    Finite temperatures;    Input-output characteristics;    Numerical results;    Operation voltage;    Single flux quantum;    Single-flux quantum pulse;    Voltage multipliers;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/871/1/012066/pdf
DOI  :  10.1088/1742-6596/871/1/012066

来源: IOP

【 摘 要 】

A double-flux-quantum amplifier (DFQA) is a voltage multiplier of quantum accuracy, which we have employed at the final stage of a single-flux-quantum (SFQ) digital-to-analog converter (DAC). We recently found that experimental input-output (IO) characteristics of DFQAs were always slightly different from numerical results assuming ideally-periodic SFQ pulse trains. That is, experimental IO characteristics obtained using an over-biasing method were gradually deteriorated near their maximum operation voltages. Numerical simulation including the over-biasing method at a finite temperature suggested that the difference was likely to be attributed to thermally-fluctuated intervals of input SFQ pulses.