Main International Collaborations:

Jyrki Piilo - Univ. of Turku, Finland

Heinz-Peter Breuer - Univ. of Freiburg, Germany

Man-Hong Yung - Aspuru-Guzik research group, Harvard University, USA


Research Overview:
Linear Optics: Using spontaneous parametric down conversion (SPDC) process in nonlinear crystal (usually BBO), we can get entangled photon pairs. Then with polarizing beam splitter (PBS) gate, we can link the photon pairs to get multi-photon entangled states. With these entangled states and conventional optical elements (wave plate, FP cavity, beam splitter, quartz plates, APD, etc) we demonstrate various quantum information protocols. Another progress is to demonstrate dynamics process of given Hamiltonian with ancilla qubit.

Self-assembled Quantum Dots: SPDC process above mentioned is probabilistic, however the cascaded process in single quantum dot may generate deterministic entangled XX-X photon pairs. We also study the spin dynamics process in quantum dots (maybe including other low-dimensional materials in future).

Solid State Quantum Memory: Rare-earth-ion doped crystal has many excellent properties as a candidate solid-state quantum memory for light, such as long coherence time, large bandwidth and strong light and matter coupling. We are working on the realization of a practical quantum memory for applications in quantum networks.


Spontaneous parametric down conversion

Quantum dots

Solid state quantum memory with rare-earth-ion doped crystals