1V脉冲驱动型交流量子电压源研究

Pulse-driven AC Josephson Voltage Standard with an Output Voltage of One Volt

脉冲驱动型交流量子电压标准ACJVS通过高速脉冲序列驱动约瑟夫森结阵芯片的方式实现宽频带交流量子电压的合成,相比于可编程型交流量子电压标准PJVS,具有免台阶切换、频谱纯净、频带宽等优点。搭建的系统主要包括8位高速脉冲码型发生器、微波放大器、直流阻断、约瑟夫森结阵芯片等。通过驱动包含4个子阵列,每个子阵列含12810个约瑟夫森结的结阵芯片,并结合4通道联合低频补偿的方式,成功产生了1 V有效值的脉冲驱动型交流量子电压,为进一步建立交流量子电压基准打下了坚实的基础。最后,展望了脉冲驱动型交流量子电压在量子阻抗桥、交流量子功率源、交流量子功率表方面的应用价值。

The AC Josephson voltage standard synthesizes quantum voltages by driving Josephson junctions using a high-speed pulse pattern generator.In comparison with the Programmable Josephson Voltage Standard,its output waveform has no step transitions,clearer spectrum and wider bandwidth.The ACJVS contains a pulse pattern generator with eight bits,a microwave amplifier,DC blocks and a Josephson junction chip.A root-mean-square voltage of one volt was achieved by driving four sub-arrays with each containing 12810 Josephson junctions.In the system,each sub-array is compensated by a low frequency current source.In the end,three possible applications of the developed system including the quantum impedance bridge,quantum power source and quantum power meter were presented.