In the past 20 years, impressive progress has been made both experimentally and
theoretically in superconducting quantum circuits, which provide a platform for manipulating …

Reciprocity is a fundamental principle in optics, requiring that the response of a transmission
channel is symmetric when source and observation points are interchanged. It is of major …

The aim of this review is to provide quantum engineers with an introductory guide to the
central concepts and challenges in the rapidly accelerating field of superconducting …

“Quantum sensing” describes the use of a quantum system, quantum properties, or quantum
phenomena to perform a measurement of a physical quantity. Historical examples of …

Quantum computers have made extraordinary progress over the past decade, and
significant milestones have been achieved along the path of pursuing universal fault-tolerant …

Quantum error correction (QEC) can overcome the errors experienced by qubits and is
therefore an essential component of a future quantum computer. To implement QEC, a qubit …

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 …

Photons at microwave and optical frequencies are principal carriers for quantum information.
While microwave photons can be effectively controlled at the local circuit level, optical …

Detecting single–photon level signals—carriers of both classical and quantum information—
is particularly challenging for low-energy microwave frequency excitations. Here we …

Amorphous solids show surprisingly universal behaviour at low temperatures. The
prevailing wisdom is that this can be explained by the existence of two-state defects within …