Электронный каталог

Статья

Kalagov, G.
Fluctuation-Induced First-Order Superfluid Transition in Unitary SU(n) Fermi Gases / G.Kalagov. – Text : electronic // Physical Review B. – 2025. – Vol. 111, No. 21. – P. 214523. – URL: https://doi.org/10.1103/tncd-kbh8.

We investigate the superfluid phase transition in an SU⁡(𝑁)-symmetric Fermi gas with 𝑁 distinct spin states using the functional renormalization group. To capture pairing phenomena beyond mean-field theory, we introduce an auxiliary bosonic field and employ the leading order of the derivative expansion of the partially bosonized effective average action. By discretizing the effective potential on a grid and numerically integrating the flow equations, we resolve the thermodynamic behavior near the transition. Our results reveal a fluctuation-induced first-order phase transition for 𝑁≥4, which is absent at the mean-field level. In the unitary regime, we provide quantitative predictions for the critical temperature as well as for the discontinuities in the superfluid gap and entropy density as functions of 𝑁. With increasing 𝑁, the critical temperature decreases, while the discontinuities become more pronounced, indicating a stronger first-order transition



ОИЯИ = ОИЯИ (JINR)2025
Спец.(статьи,препринты) = С 326.3 - Ферми-системы. Спиновые системы