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arXiv · 0711.1562

Universal Fermi Gas with Two- and Three-Body Resonances

Yusuke Nishida·Dam Thanh Son·Shina Tan
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Abstract

We consider a Fermi gas with two components of different masses, with the s-wave two-body interaction tuned to unitarity. In the range of mass ratio 8.62<M/m<13.6, it is possible for a single contact interaction between heavy fermions to produce a resonance in a three-body channel. The resulting system is scale invariant and has universal properties, and is very strongly interacting. When M/m is slightly above the lower limit 8.62, the ground state energy of a 2:1 mixture of heavy and light fermions is less than 2% of the energy of a noninteracting gas with the same number densities. We derive exact relationships between the pressures of the unitary Fermi gases with and without three-body resonance when the mass ratio is close to the critical values of 8.62 and 13.6. Possible experimental realization with cold atoms in optical lattices is discussed.

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Yusuke Nishida, Dam Thanh Son, Shina Tan. 2008-02-28. Universal Fermi Gas with Two- and Three-Body Resonances. https://doi.org/10.1103/physrevlett.100.090405

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