Polarons and molecules in a Fermi gas with orbital Feshbach resonance

Jin-Ge Chen, Tian-Shu Deng, Wei Yi, Wei Zhang
2016 Physical Review A  
We study the impurity problem in a gas of ^173Yb atoms near the recently discovered orbital Feshbach resonance. In an orbital Feshbach resonance, atoms in the electronic ground state ^1S_0 interact with those in the long-lived excited ^3P_0 state with magnetically tunable interactions. We consider an impurity atom with a given hyperfine spin in the ^3P_0 state interacting with a single-component Fermi sea of atoms in the ground ^1S_0 manifold. Close to the orbital Feshbach resonance, the
more » ... y can induce collective particle-hole excitations out of the Fermi sea, which can be regarded as the polaron state. While as tuning toward the BEC regime of the resonance, a molecular state becomes the ground state of the system. We show that a polaron to molecule transition exists in ^173Yb atoms close to the orbital Feshbach resonance. Furthermore, due to the spin-exchange nature of the orbital Feshbach resonance, the formation of both the polaron and the molecule involve spin-flipping processes with interesting density distributions among the relevant hyperfine spin states. We show that the polaron to molecule transition can be detected using Raman spectroscopy.
doi:10.1103/physreva.94.053627 fatcat:lmpjt5pp4ng5revyqv4duprrjm