论文标题
迈向高效的宽带超导量子记忆
Towards highly efficient broadband superconducting quantum memory
论文作者
论文摘要
微波量子记忆有望用于嘈杂的中间尺度超导量子计算机的高级功能。现有的微波量子记忆方法缺乏高效率，较长的存储时间，无噪声和多Qubit能力的完整组合。在这里，我们报告有效的微波宽带多模量子内存。记忆存储在八个Coplanar超导谐振器的片上系统中单个光子级微波辐射的两种光谱模式。单模式存储在单个光子能量时显示出高达$ 60 \ pm 3 \％$的功率效率，并且在较高强度下的功率效率超过$ 73 \ pm 3 \％$。所证明的效率是比先前报道的多模微波量子记忆大的数量级。连贯的状态量子层析成像证实了存储的无噪声特征。展示的结果为进一步提高效率的方式铺平了道路，因此为超导量子电路构建了实用的多模微波记忆。
Microwave quantum memory promises advanced capabilities for noisy intermediate-scale superconducting quantum computers. Existing approaches to microwave quantum memory lack complete combination of high efficiency, long storage time, noiselessness and multi-qubit capacity. Here we report an efficient microwave broadband multimode quantum memory. The memory stores two spectral modes of single photon level microwave radiation in on-chip system of eight coplanar superconducting resonators. Single mode storage shows a power efficiency of up to $60\pm 3\%$ at single photon energy and more than $73\pm 3\%$ at higher intensity. The demonstrated efficiency is an order of magnitude larger than the previously reported multimode microwave quantum memory. The noiseless character of the storage is confirmed by coherent state quantum process tomography. The demonstrated results pave the way to further increase in efficiency and hence building a practical multimode microwave memory for superconducting quantum circuits.
