Quantum-mechanical effects at the macroscopic level were first explored in Josephson-
junction-based superconducting circuits in the 1980s. In recent decades, the emergence of …

In superconducting quantum computing, qubit state information is conveyed via low-power
microwave fields. As such, ultralow-noise microwave amplification plays a central role in …

Quantum-limited microwave parametric amplifiers are genuine key pillars for rising quantum
technologies and, in general, for applications that rely on the successful readout of weak …

Degenerate parametric amplifiers (DPAs) exhibit the unique property of phase-sensitive
gain and can be used to noiselessly amplify small signals or squeeze field fluctuations …

A microwave amplifier combining noise performances as close as possible to the quantum
limit with large bandwidth and high saturation power is highly desirable for many solid-state …

Quantum-limited Josephson parametric amplifiers are crucial components in circuit QED
readout chains. The dynamic range of state-of-the-art parametric amplifiers is limited by …

With a large portfolio of elemental quantum components, superconducting quantum circuits
have contributed to advances in microwave quantum optics. Of these elements, quantum …

Masers once represented the state of the art in low-noise microwave amplification
technology but eventually became obsolete due to their need for cryogenic cooling. Masers …

Qubit readout is an indispensable element of any quantum information processor. In this
work, we experimentally demonstrate a nonperturbative cross-Kerr couplingbetween a …

We introduce a near-quantum-limited amplifier with a large tunable bandwidth and high
dynamic range—the Josephson array-mode parametric amplifier (JAMPA). The signal and …