Brevik Justus A, Flowers-Jacobs Nathan E, Fox Anna E, Golden Evan B, Dresselhaus Paul D, Benz Samuel P
National Institute of Standards and Technology, Boulder, CO 80305 USA.
IEEE Trans Appl Supercond. 2017 Apr;27(3). doi: 10.1109/TASC.2017.2662708. Epub 2017 Feb 1.
We describe the implementation of new commercial pulse-bias electronics that have enabled an improvement in the generation of quantum-accurate waveforms both with and without low-frequency compensation biases. We have used these electronics to apply a multilevel pulse bias to the Josephson arbitrary waveform synthesizer and have generated, for the first time, a quantum-accurate bipolar sinusoidal waveform without the use of a low-frequency compensation bias current. This uncompensated 1 kHz waveform was synthesized with an rms amplitude of 325 mV and maintained its quantum accuracy over a1.5 mA operating current range. The same technique and equipment was also used to synthesize a quantum-accurate 1 MHz sinusoid with a 1.2 mA operating margin. In addition, we have synthesized a compensated 1 kHz sinusoid with an rms amplitude of 1 V and a 2.7 mA operating margin.
我们描述了新型商用脉冲偏置电子设备的应用，它能够在有无低频补偿偏置的情况下，改进量子精确波形的产生。我们使用这些电子设备对约瑟夫森任意波形合成器施加多级脉冲偏置，并首次在不使用低频补偿偏置电流的情况下，产生了量子精确的双极正弦波形。这种未补偿的1kHz波形的均方根幅度为325mV，在1.5mA的工作电流范围内保持了其量子精度。同样的技术和设备还被用于合成具有1.2mA工作裕度的量子精确1MHz正弦波。此外，我们还合成了均方根幅度为1V、工作裕度为2.7mA的补偿1kHz正弦波。
