Speaker: César Cabrera
Affiliation: Institut für Laser-Physik
Date: Wednesday, 17 September 2025 at 12:00
Location: Seminar Room, Serrano 113b
Ultracold Fermi gases offer a powerful route to explore fermionic pairing in strongly correlated systems. During my talk, I will present recent results on the BEC-BCS crossover in two complementary regimes. First, we experimentally investigate a two-dimensional fermionic superfluid confined in an anisotropic trap with short-range interactions. By modulating the confinement, we excite the amplitude mode of the order parameter and reveal its hybridization with spatial modes of the trap (1). Additionally, by exploiting the eigenstates of the confining potential, we study impurity physics and realize a stable, repulsive Bose polaron, benchmarking our results against T-matrix and Quantum Monte Carlo methods. In the second part of my talk, I will present a new platform to explore the crossover in systems with long-range dipolar interactions, using a dipolar Fermi mixture. This approach enables the formation of dipolar dimers and opens the path to anisotropic and topological superfluid phases. Overall, our current work aims to demonstrate how interaction range and dimensionality influence collective dynamics, pairing, and the emergence of quantum phases in ultracold Fermi gases.
(1) C.R.Cabrera, et al. , Phys. Rev. Research 7, L032018 (2025)