Transmitting quantum states of single photons from one location to another is one of the most important routines of any quantum communication system. Our current research areas in quantum communication include single photon creation, transmission, storage, transduction and detection - these are the fundamental building blocks for the quantum communication systems of the future. In such systems, one will encode information into strategically created single photons (flying Qubits), transmit them and interface them with an atomic quantum memory (stationary Qubits) for storage and processing. A typical example of such systems are quantum repeaters that can extend operation distance for quantum key distribution (QKD) systems, and/or connect quantum computers to form the large-scale quantum networks of the future. Our current research is focused on the following areas: (1) Entangled photon pair sources: Based on parametric frequency down conversion or four-wave mixing, single photon pairs are generated in a resonant cavity to ensure the linewidth is sufficiently narrow to match the atomic systems for high efficiency; (2) Quantum memories: Our current approach is based on electromagnetically induced transparency (EIT) using warm atomic vapor or cold atomic ensamples in a magneto-optical trap (MOT); (3) Quantum interface: By using nonlinear optical materials, wavelengths of the generated single photons can be converted between atomic transition lines for storage and processing and telecommunication bands for long distance transmission; (4) Bell state measurement: The measurement results provide information for quantum teleportation and; (5) Electronics and software for final integration of a quantum repeater.

 

key words

Quantum communication; Quantum computing; Quantum repeater; Quantum network; Quantum teleportation; Quantum memory, Entangled photon source; Photon interface; Single photon detection;

Citizenship:  Open to U.S. citizens

Level:  Open to Postdoctoral applicants