| Abstract: | Cavity Quantum Electrodynamics (CQED) - in the spirit of the "photon box" thought experiment imagined by Bohr and Einstein - illustrates the fundamental principles of quantum theory. A beam of Rydberg atoms is used to manipulate and probe non-destructively microwave photons trapped in a very high-Q superconducting cavity. We realize ideal quantum non-demolition (QND) measurements of photon numbers, observe the radiation quantum jumps due to cavity relaxation and prepare non-classical fields such as photon number states (Fock states) and Schroedinger cat states. The reconstruction of these states and the study of their evolution, either spontaneous, or controlled by quantum feedback procedures, provides a striking illustration of the phenomenon of decoherence responsible for the transition from the quantum to the classical worlds. The colloquium will present a broad overview, and the two specialized lectures will give more details on specific aspects of this research which may find applications in quantum information. Serge Haroche's main research areas are in quantum optics and experimental quantum information science. He has received numerous prizes and awards, including the Humboldt prize, the C. Townes award (from the OSA), the gold medal of the french CNRS, the Michelson medal from the Franklin Institute, the quantum electronics and optics prize of the European Physical Society. Professor Serge Haroche is a member of the French Academy of Sciences, and a professor at the College de France where he succeeded Claude Cohen-Tannoudji. |
