Abstract of the talk
Recent experiments have realized an all-optical photon transistor using a cold atomic gas. This approach relies on electromagnetically induced transparency (EIT) in conjunction with the strong interaction among atoms excited to high-lying Rydberg states. The transistor is gated via a so-called Rydberg spinwave, in which a single Rydberg excitation is coherently shared by the whole ensemble. In its absence the incoming photon passes through the atomic ensemble by virtue of EIT while in its presence the photon is scattered rendering the atomic gas opaque. An important current challenge is to preserve the coherence of the Rydberg spinwave during the operation of the transistor, which would enable for example its coherent optical read-out and its further processing in quantum circuits. With a combined field theoretical and quantum jump approach and by employing a simple model description we investigate systematically and comprehensively how the coherence of the Rydberg spinwave is affected by photon scattering. With large-scale numerical calculations we show how coherence becomes increasingly protected with growing interatomic interaction strength. The theoretical model is experimentally verified recently.
If time permits, I will also introduce our recent work on how one can realize supersolid phases in optical lattices with the strongly interacting Rydberg atoms.
Biography of the Speaker
Dr. Weibin Li is an Assistant Professor at the School of Physics and Astronomy at the University of Nottingham. He obtained his Ph.D. in atomic and molecular physics, in 2007 from Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences. He had his first postdoctoral position at Max-Planck-Institute for the Physics of Complex Systems, Dresden, Germany. He moved to the University of Nottingham as a Marie-Curie Intra-European Fellow and then obtained a Nottingham Advanced Research Fellowship. He has been promoted as an assistant professor from May 2016.
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