Quantum cluster expansion study of BEC in three-component Fermi gas

We study the system of a mixture of interconvertible monomers, dimers and trimers in a three-component ultracold Fermi gas, where dimers and trimers are formed in a two- and three-particle bound state, respectively. We use the Lee-Yang quantum cluster expansion method to calculate the grand partition function and estimate the transition temperature of Bose-Einstein condensation (BEC) of the dimers. We point out that provided the number density of particles is above the critical value, the dimers show a BEC transition at a finite temperature.