In this thesis, measurements on superconducting electrical circuits that exhibit quantum mechanical effects are presented. Nonlinear superconducting circuits can be regarded as artificial atoms with energy spectra that can be engineered. The artificial atoms can be used as quantum bits for quantum computation. By coupling the artificial atoms to the electromagnetic field inside a transmission l...

My first thoughts in writing this lecture are about the young women and young men who are beginning their lives in science: students and those beginning scientific research. I have been in experimental scientific research for 45 years; I have done some good experiments of which the best was the discovery of the tau leptonj I have followed research directions that turned out to be uninteresting ...

We consider three-loop radiative-recoil corrections to hyperfine splitting in muonium generated by the diagrams with electron and muon vacuum polarizations. We calculate single-logarithmic and nonlogarithmic contributions of order alpha;{3}(m/M)E_{F} generated by gauge invariant sets of diagrams with electron and muon polarization insertions in the electron and muon factors. Combining these cor...

Photon splitting is a QED process that can potentially suppress pair production in the inner magnetosphere of a pulsar with a super-strong magnetic field, and hence, may quench radio emission from these objects. While it is unknown how many splitting modes really operate in supercritical fields, we derive gap parameters of a high magnetic field pulsar for both the vacuum-type gap and the space-...

Achieving control over light-matter interaction in custom-tailored nanostructures is at the core of modern quantum electrodynamics. In strongly and ultrastrongly coupled systems, the excitation is repeatedly exchanged between a resonator and an electronic transition at a rate known as the vacuum Rabi frequency ΩR. For ΩR approaching the resonance frequency ωc, novel quantum phenomena including ...

Systems of strongly interacting atoms and photons, which can be realized wiring up individual cavity QED systems into lattices, are perceived as a new platform for quantum simulation. While sharing important properties with other systems of interacting quantum particles, here we argue that the nature of light-matter interaction gives rise to unique features with no analogs in condensed matter o...

We study a system of single qubit (or few qubits) interacting with soft-mode bosonic field. Considering an extended version the Rabi model both parity-conserving and parity-violating interactions, we disclose complex arrangement quantum phase transitions in ground- excited-state domains. An experimentally testable signature some these is dynamical stabilization fully factorized qubit-field stat...

When the strength of light–matter interaction (the Rabi splitting) in mesocavities is comparable to energy spacing between cavity modes, an exciton mode coupled simultaneously a number optical modes. It has recently been demonstrated that nonmonotonic dependence population polariton states on pump intensity possible. Here, it shown additional quasistationary state may appear hysteresis region a...