Generation, Measurement, and Preservation of Entanglement Using Cavity QED And Optical Lattices

Miami University, Oxford OH

Investigators

Abstract

Examination of a simple open system, atoms in a driven cavity, with external trapping potentials, including spontaneous emission and cavity loss, will be investigated. The work will explore how to quantify entanglement for mixed quantum states, which is still an open question. A system with many atoms will also facilitate studies of multipartite entanglement, also not well understood to date. The project begins with studies of entanglement in single atom cavity QED using correlation functions, to systems of a few atoms, trapped inside potential wells in an optical cavity. This will extend our knowledge of entanglement in open quantum systems, and multipartite systems. Probabilistic generation of entanglement and its distribution, as studied experimentally by the groups of Lukin, Kimble and Kuzmich, will be treated. Feedback to protect quantum states has been experimentally demonstrated in cavity QED. Many feedback and control schemes utilize a Gaussian noise approximation; the work will go beyond that, looking at systems of a few atoms/photons. In the second phase of the project investigations of atom cavity states useful for various cluster state and one-way quantum computation schemes, as well as implementations of quantum networks of CQED systems, will be studied. The cavity may serve several purposes: the strong coupling to the optical mode may be used to obtain information on the atomic state (by monitoring, e.g., the transmitted light) that might be difficult to access otherwise; it may also provide a way to manipulate the joint atomic state, and prepare interesting or useful entangled atomic superpositions. Finally, quantum information processing with cavities outside the strong coupling limit, will be examined, as they are much easier to implement experimentally. Close collaboration with the experimental group of Luis Orozco at the University of Maryland, and others, will help focus the work on physically realizable schemes.