2019/01/31 by Nelson Darkwah Oppong, Luis Riegger, Oscar Bettermann +5 · 1 citation
Physics and Astronomy · #cond-mat.quant-gas
paper · pdf · doi:10.1103/physrevlett.122.193604
published as Phys. Rev. Lett. 122, 193604 (2019) · 6 pages, 4 figures; Supplementary Material
arxiv created 2019/05/20 · arxiv updated 2019/05/21
We report on the experimental observation of multiorbital polarons in a two-dimensional Fermi gas of 173Yb atoms formed by mobile impurities in the metastable 3P0 orbital and a Fermi sea in the ground-state 1S0 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.