Superfluidity in multicomponent fermions via functional renormalization group

Seminars

Bogoliubov Laboratory of Theoretical Physics

Seminar “Theory of Condensed Matter”

Date and Time: Tuesday, 19 December 2023, at 4:00 PM

Venue: Blokhintsev Lecture Hall, Bogoliubov Laboratory of Theoretical Physics, online on Zoom

Seminar topic: “Superfluidity in multicomponent fermions via the functional renormalization group”

Speaker: Georgii Kalagov

Abstract:

We investigate the essential characteristics of the phase transition leading to the superfluid order, which is hypothesized to take place in large spin fermionic systems. To accomplish this, we analyze the bosonic field theory governing fluctuations of the complex skew-symmetric rank-2 tensor order parameter in the vicinity of the transition. Through the application of the functional renormalization group, we non-perturbatively determine the scale-dependent behavior of the theory’s couplings. Our findings reveal the presence of a fluctuation-induced first-order phase transition. In the regime of weak coupling, the jump in the order parameter is relatively small, resulting in the emergence of a new phase that forms in a nearly continuous manner. Conversely, in the regime of strong coupling, the transition exhibits a noticeable discontinuity, making the phase change more discernible.