Flouqet engineering and quasi-particle properties in a stronglyinteracting Fermi gas

Abstract

• Degenerate Fermi gases have been used extensively in recent years to study complex many-body phenomena. Our labratory
  works with 40K atoms that have a convenient Feshbach resonance that allows us to tune the interactions. In this seminar, I
  will present two projects I was involved in. In the first project, we employ external periodic driving to generate a flat trap for
  the gas. This technique, known as Floquet engineering, allows the creation of novel potentials and study out of equilibrium
  phases. However, it also tends to heat up the system, which may limit its usefulness. Here, we studied the heating rate and
  showed that it is negligible at a high enough modulation frequency. In particular, using deep learning-assisted data analysis,
  we have proved the existence of a fermionic condensate in externally modulated strongly-interacting gas.
• 
  In a second project, we have used Raman excitation to probe the properties of quasi-particles in a balanced gas.These quasiparticles
• possess a long lifetime and well-defined dispersion, which we aim to characterize by monitoring their transfer rate
• by a two-photon process. I will present preliminary data from which we extract the quasi-particle's spectral weight (residue)
  and energy for different interaction strengths.