Fermi polarons in two dimensions
  We theoretically analyze inverse radiofrequency (rf) spectroscopy experiments in two-component Fermi gases. We consider a small number of impurity atoms interacting strongly with a bath of majority atoms. In two-dimensional geometries we find that the main features of the rf spectrum correspond to an attractive polaron and a metastable repulsive polaron. Our results suggest that the attractive polaron has been observed in a recent experiment [Phys. Rev. Lett. 106, 105301 (2011)]. 
Richard Schmidt, Tilman Enss, Ville Pietil\"a, and Eugene Demler
cond-mat.quant-gas cond-mat.str-el quant-ph