Welcome to the page of Wei Yi's Cold Atom Theory group at the University of Science and Technology of China.

Cold Atom Theory USTC

 











 

 

  1. Wei Yi (易为)

  2. Professor

  3. Key Laboratory of Quantum Information, CAS

  4. University of Science and Technology of China

  5. 96 Jinzhai Rd., Hefei

  6. Anhui, 230026, P. R. China


  7. Tel: +86-551-63603257
    Email: wyiz@ustc.edu.cn
    Office: 501

   > Homeshapeimage_10_link_0


We are mostly interested in the theoretical study of quantum simulation in cold atomic gases and other related physical systems. As a practical alternative to the universal quantum computers, a quantum simulator is a highly controllable device that can be used to investigate the properties of another more complicated quantum system whose characterization is typically beyond the capability of classical computers.

Featuring a clean environment and highly tunable parameters, an ultracold atomic gas is an ideal platform for quantum simulation. Since the realization of Bose-Einstein condensates in ultracold Rubidium and Cesium atoms in 1995, the investigation of ultracold atomic gases has developed into one of the most active fields in physics. Although experimentally, cold atomic gases are typically extremely dilute with short-range interactions, they have been used to study strongly interacting strongly correlated many-body physics, thanks to powerful tools such as the Feshbach resonance and the optical lattice potentials. So far, quantum simulations of various interesting models, such as the BCS-BEC crossover and the Bose-Hubbard model, have been successfully carried out in ultracold atomic gases.

Presently, we are working on the following subjects:

Synthetic gauge field in cold atoms


The recent realization of synthetic gauge field in ultracold atomic gases provides us with a powerful tool of quantum control. Combined with existing techniques such as the Feshbach resonance and the optical lattice potential, synthetic gauge field greatly extends the possibility of engineering and probing novel phenomena and exotic phases in ultracold atomic gases. We are particularly interested in the effects of synthetic spin-orbit coupling, a non-Abelian gauge field, in ultracold atomic gases. As spin-orbit coupling modifies the single-particle dispersion spectra, both the few-body and many-body properites of the system can become quite intriguing.

Few-body physics


Few-body problems, which, in the early days, were mainly studied in nuclear systems, have now received much attention and generated tremendous excitement in the field of cold atoms. A famous example is the Efimov state, which was originally predicted in nuclear physics in 1970s, and has only recently been observed in experiments by the Innsbruck group in ultracold atomic gases. A primary reason that few-body physics is important and interesting is that, in a dilute system such as a cold atomic gas, many-body effects are typically based on, and frequently determined by, few-body physics. Hence, a better knowledge of the building blocks allows one to gain better understanding of the whole system, and to engineer exotic many-body phases.

Dynamical processes


Cold atomic gases are ideal for the study of quantum dynamical processes. A naturally isolated system with tunable parameters, it has already been used to investigate various quantum quench processes in closed systems. Coupled with cavity or other cold atomic gases, it is also possible to simulate dissipative many-body quantum dynamics. Most interestingly, due to the flexibility of cold atoms, one may entertain the possibility of reservoir engineering, such that the quantum dynamical processes proceed in a controllable manner.

And more...



Research interest