Atomic, Molecular, and Optical Physics Seminar
Progress Toward Generating, Storing, and Communicating Single-Photon States Using Coherent Atomic Memory
I will report on our progress toward generation, storage, and communication of single-photon states using atomic memory. Specifically, I will describe experiments demonstrating conditional generation of single-photon pulses of light with controllable propagation direction, timing, and pulse shapes. The approach is based on preparation of an atomic ensemble in a state with a desired number of atomic spin excitations, which is later converted into a photon pulse by exploiting long-lived coherent memory for photon states and electromagnetically induced transparency (EIT). In addition, I will describe investigations of EIT at the single-photon level. Conditionally generated single-photon states are transmitted through a second atomic ensemble, and we observe that the nonclassical nature of the transmitted field is only preserved when its frequency is within the EIT transparency window of the ensemble. In addition, we observe a time delay of these single-photon pulses due to the reduced group velocity associated with EIT, and observe "light storage" by dynamically reducing the group velocity to zero. Finally, I will discuss the prospects for long-distance quantum communication using these techniques.
Monday, October 10, 2005
Gant Science Complex