The research program explores quantum dynamical processes for strong radiative interactions between one atom and the electromagnetic field of a microscopic optical cavity. The setting for these investigations is cavity quantum electrodynamics (cavity QED) in a domain of strong coupling in which the time scale for coherent quantum evolution of an interacting atom and photon is much shorter than the times scale for irreversible decay.
Capabilities are being developed to trap single atoms within the evanescent fields of microscopic optical resonators with extremely low optical losses, thereby enabling cavity QED with critical atom and photon numbers significantly beyond current and projected values for conventional optical cavities. With a single atom-cavity system, nonlinear interactions between single photon pulses are investigated, including entangling operations between `flying photons' and quantum non-demolition measurements of single-photon fields. Multiple atom-cavity systems are being linked together for investigations of the creation and distribution of quantum entanglement among atom-cavity systems at remote locations by way of photon-mediated interactions.
The research program propels optical physics beyond traditional nonlinear optics and laser physics into a regime with quantum dynamical processes now involving atoms and photons taken one by one. On the one hand, the research extends knowledge of fundamental radiative processes for the interaction of light and matter. On the other hand, the research endeavors to harness these basic radiative processes to create new scientific possibilities and technical capabilities in Quantum Optics and Quantum Information Science (QIS).
The broader impacts of the research program include applications ranging from measurements of fundamental constants to the development of novel semiconductor devices to the deterministic generation of entangled photon pairs. The research contributes to the realization of complex quantum networks by way of interactions in cavity QED. Such capabilities could have broad impact, including for quantum computation, communication, and metrology. The attainment of strong coupling in atomic physics has inspired similar investigations in a wide class of physical systems, including quantum dots coupled to micro-pillars and photonic bandgap cavities and Cooper-pairs interacting with superconducting resonators.
The research program makes contributions to education and human resources in areas of immediate importance to the nation's scientific and technological future by way of advanced training of undergraduates, graduate students, and postdoctoral scholars. With the end of scalability of conventional silicon-based information technology on the horizon, such investments in the training of talented young scientists are vitally important.
