Observation of Coherent Multiorbital Polarons in a Two-Dimensional Fermi Gas.

@article{DarkwahOppong2019ObservationOC,
  title={Observation of Coherent Multiorbital Polarons in a Two-Dimensional Fermi Gas.},
  author={Nelson Darkwah Oppong and Luis Riegger and Oscar Bettermann and Moritz H{\"o}fer and Jesper Levinsen and Meera M. Parish and Immanuel Bloch and Simon F{\"o}lling},
  journal={Physical review letters},
  year={2019},
  volume={122 19},
  pages={
          193604
        }
}
We report on the experimental observation of multiorbital polarons in a two-dimensional Fermi gas of ^{173}Yb atoms formed by mobile impurities in the metastable ^{3}P_{0} orbital and a Fermi sea in the ground-state ^{1}S_{0} 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… 

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