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Pair condensation and bound states in fermionic systems

Armen Sedrakian·John W. Clark
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Abstract

We study the finite temperature-density phase diagram of an attractive fermionic system that supports two-body (dimer) and three-body (trimer) bound states in free space. Using interactions characteristic for nuclear systems, we obtain the critical temperature T_c2 for the superfluid phase transition and the limiting temperature T_c3 for the extinction of trimers. The phase diagram features a Cooper-pair condensate in the high-density, low-temperature domain which, with decreasing density, crosses over to a Bose condensate of strongly bound dimers. The high-temperature, low-density domain is populated by trimers whose binding energy decreases toward the density-temperature domain occupied by the superfluid and vanishes at a critical temperature T_c3 > T_c2.

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Armen Sedrakian, John W. Clark. 2006-03-07. Pair condensation and bound states in fermionic systems. https://doi.org/10.1103/physrevc.73.035803

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