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arXiv · 1407.5438

Pairing in Asymmetric Many-Fermion Systems: Functional Renormalisation Group Approach

Boris Krippa
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Abstract

Functional renormalisation group approach is applied to a imbalanced many- fermion system with a short-range attractive force. Composite boson field is introduced to describe the pairing between different flavour fermions. A set of approximate flow equations for the effective couplings is derived and solved. We identify the critical values of mass and particle number density mismatch when the system undergoes a phase transition to a normal state and determine the phase diagram both at unitary regime and nearby.

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Boris Krippa. 2015-01-24. Pairing in Asymmetric Many-Fermion Systems: Functional Renormalisation Group Approach. https://doi.org/10.1016/j.physletb.2015.03.057

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