Dr. Duan's research focuses on theory and implementation of quantum information science. Quantum information science investigates how to characterize the mysterious concept of "entanglement" arising from quantum mechanics, how to use it as a resource for applications in various information processing tasks, and how to achieve better understanding of quantum many-body systems based on this concept. They study strongly correlated many-body phenomena arising from the ultracold atomic system. Investigation of ultracold bosonic or fermionic atomic gas remains one of the most active fields of physics ever since the achievement of Bose-Einstein condensation in 1995. Recently, studies in this field evolve into a new phase when the interactions between the atoms can be manipulated at will to realize various kinds of strongly correlated many-body systems.