Seminar "Unitary few- and many-body problems in ultracold Fermi gases" Prof. Shimpei Endo, Tohoku University
Unitary Fermi gases are prime examples of strongly correlated quantum systems, realized in cold atoms with the Feshbach resonance. They show behavior quite different from Bose systems due to the Pauli principle: the unitary Fermi gases can be realized stably and their equations of states have been observed with high precision, while the unitary Bose system suffers from the strong 3-body loss originating from the formation of 3-body bound states, Efimov states. In this talk, I present few- and many-body studies of the unitary Fermi systems. Firstly, I talk about 3-body and 4-body studies of the Fermi system, particularly the mass-imbalanced Fermi system. The role of the Pauli principle can be “controlled” by varying the mass ratios, and presence/absence of the Efimov trimers and tetramers can be changed by the mass ratio. Then, I will explain how these few-body studies can be applied to the many-body problem using the virial expansion, with which we can accurately obtain high-temperature equation of state of the unitary gases.
Looking forward to seeing many of you at the seminar.
-Quantum Systems Unit / Busch Unit