We report on the experimental observation of multiorbital polarons in a two-dimensional Fermi gas of Yb173 atoms formed by mobile impurities in the metastable P03 orbital and a Fermi sea in the ground-state S01 orbital. We spectroscopically probe the energies of attractive and repulsive polarons close to an orbital Feshbach resonance and characterize their coherence by measuring the quasiparticle residue. For all probed interaction parameters, the repulsive polaron is a long-lived quasiparticle with a decay rate more than 2 orders of magnitude below its energy. We formulate a many-body theory, which accurately treats the interorbital interactions in two dimensions and agrees well with the experimental results. Our work paves the way for the investigation of many-body physics in multiorbital ultracold Fermi gases.
- Superfluid phase