A near-quantum-limited Josephson traveling-wave parametric amplifier
A near-quantum-limited Josephson traveling-wave parametric amplifier
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DOI：
10.1126/science.aaa8525
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发表时间：
2015-10-16
期刊：
影响因子：
56.9
通讯作者：
Siddiqi, I.
中科院分区：
文献类型：
--
作者：
Macklin, C.;O'Brien, K.;Siddiqi, I.
检测单光子能级信号-经典和量子信息的载体-对于低能微波频率激励特别具有挑战性。本文介绍了一种基于约瑟夫森结传输线的超导放大器。与目前的驻波参量放大器不同，这种行波结构在几千兆赫的带宽上稳健地实现了高增益，具有足够的动态范围来读出20个超导量子比特。为了实现这一性能，我们引入了一种亚波长共振相位匹配技术，该技术能够创建具有独特色散关系的非线性微波器件。我们用弱测量对放大器进行了基准测试，获得了75%的高量子效率(70%包括约瑟夫森放大器后面的放大器添加的噪声)。这种约瑟夫森放大器具有基于紧凑集总元件的灵活设计，在微波计量和量子光学中具有广泛的适用性。
Detecting single-photon level signals-carriers of both classical and quantum information-is particularly challenging for low-energy microwave frequency excitations. Here we introduce a superconducting amplifier based on a Josephson junction transmission line. Unlike current standing-wave parametric amplifiers, this traveling wave architecture robustly achieves high gain over a bandwidth of several gigahertz with sufficient dynamic range to read out 20 superconducting qubits. To achieve this performance, we introduce a subwavelength resonant phase-matching technique that enables the creation of nonlinear microwave devices with unique dispersion relations. We benchmark the amplifier with weak measurements, obtaining a high quantum efficiency of 75% (70% including noise added by amplifiers following the Josephson amplifier). With a flexible design based on compact lumped elements, this Josephson amplifier has broad applicability to microwave metrology and quantum optics.