Theoretical Quantum Optics and Quantum Information

Wittgenstein Award Z 30 Theoretical Quantum Optics and Quantum Information Peter ZOLLER 19.06.1998 In quantum optics we are interested in (i) the development of theoretical tools to describe of open and driven quantum systems, and (ii) the investigation of specific model systems such as laser cooled trapped atoms and ions, and to cavity QED. Of particular interest are applications to quantum informations, including the development of theoretical concepts and implementation of quantum computers and in quantum communication.

Research supported by the Wittgenstein Award in the period 1998 - 2005 focused on theoretical quantum optics, in particular on connections between quantum optics and quantum information, and the developing interface of quantum optics and atomic physics, and condensed matter physics. The success story of quantum optics during the last ten years is largely based on progress in gaining quantum control on the single quantum level while suppressing unwanted interactions with the environment causing decoherence. These achievements are illustrated by storage and laser cooling of single trapped ions and atoms, and the manipulation of single photons in Cavity QED, opening the field of engineering interesting and useful quantum states. In the mean time the frontier has moved towards building larger composite systems of a few atoms and photons, while still allowing complete quantum control of the individual particles. The new physics to be studied in these systems is based on entangled states, both from a fundamental point of testing quantum mechanics for larger and larger systems, but also in the light of possible new applications like quantum information processing or precision measurements. While the research performed was theoretical in nature, an important component has been on implementation of quantum information processing and communication in specific systems with methods of quantum optics and atomic physics. In fact, the research conducted with the Wittgenstein Award has stimulated key experimental developments in quantum optics and atomic physics, and the publications have set trends for theoretical research in this field. This includes in particular our ideas and development of theoretical models and proposals for quantum computing and quantum communications with trapped atoms and ion, cavity QED, and atomic ensembles. Further ideas include building of strongly correlated lattice gas models with cold atoms in optical lattices as a new way of simulating strongly correlated condensed matter models, has in particular also opened connections between physics with cold atoms and the theoretical condensed matter community. Identifying interdisciplinary connections between various fields has been the characteristic feature of our research effort. Recent work has also moved directly with quantum optical ideas and theoretical techniques into solid state physics, where examples are provided by our interest in nano-ion traps, nanomechanical systems and quantum dots.