论文标题
图像充电检测的低温扩增，用于读取液体氦气量子状态的量子状态
Cryogenic amplification of image-charge detection for readout of quantum states of electrons on liquid helium
论文作者
论文摘要
准确检测量子状态是量子计算开发的重要步骤。液态氦气上电子量子状态的图像荷尔布检测可能可能用于读数单电子量子量子；但是，由于增加噪声而引起的低灵敏度阻碍了其在高保真和带宽（BW）应用中的使用。提高读数准确性和带宽的一种方法是在信号源附近使用低温放大，以最大程度地减少流浪电容的影响。我们通过实验表明，在位于稀释冰箱的静止板的第一阶段，低功率耗散为90μW，在4 K板的第二阶段的高增益为40 dB。不同阶段和输出设备之间的良好阻抗匹配可确保在较大频率范围内高BW和恒定增益。将检测到的图像充电信号进行比较的单阶段和两阶段扩增方案。
Accurate detection of quantum states is a vital step in the development of quantum computing. Image-charge detection of quantum states of electrons on liquid helium can potentially be used for the readout of a single-electron qubit; however, low sensitivity due to added noise hinders its usage in high fidelity and bandwidth (BW) applications. One method to improve the readout accuracy and bandwidth is to use cryogenic amplifications near the signal source to minimize the effects of stray capacitance. We experimentally demonstrate a two-stage amplification scheme with a low power dissipation of 90 μW at the first stage located at the still plate of the dilution refrigerator and a high gain of 40 dB at the second stage located at the 4 K plate. The good impedance matching between different stages and output devices ensure high BW and constant gain in a wide frequency range. The detected image-charge signals are compared for one-stage and two-stage amplification schemes.
