Ultrastrong coupling between light and matter has, in the past decade, transitioned from a
theoretical idea to an experimental reality. It is a new regime of quantum light–matter …

Recent experiments have demonstrated that light and matter can mix together to an extreme
degree, and previously uncharted regimes of light-matter interactions are currently being …

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

In quantum electrodynamics, the choice of gauge influences the form of light–matter
interactions. However, gauge invariance implies that all physical results should be …

We show how analogs of a large number of well-known nonlinear-optics phenomena can be
realized with one or more two-level atoms coupled to one or more resonator modes …

This article reviews theoretical methods developed in the last decade to understand cavity
quantum electrodynamics in the ultrastrong‐coupling regime, where the strength of the light …

We propose a superconducting circuit to implement a two-photon quantum Rabi model in a
solid-state device, where a qubit and a resonator are coupled by a two-photon interaction …

A quantum system weakly coupled to a zero-temperature environment will relax, via
spontaneous emission, to its ground-state. However, when the coupling to the environment …

The interaction of light and matter at the single-photon level is of central importance in
various fields of physics, including, eg, condensed matter physics, astronomy, quantum …

We study the dynamical Casimir effect using a fully quantum-mechanical description of both
the cavity field and the oscillating mirror. We do not linearize the dynamics, nor do we adopt …