We study a highly imbalanced Fermi gas in a one-dimensional (1D) optical lattice from the polaronic point of view. The time-evolving block decimation algorithm is used to calculate the ground state and dynamics of the system. We find polaronic behaviour qualitatively similar to that in the recent experiment by Schirotzek et al (2009 Phys. Rev. Lett. 102 230402), where radio-frequency (rf) spectroscopy was used to observe polarons in 3D space. In the weakly interacting limit, our exact results are in excellent agreement with a polaron ansatz, and in the strongly interacting limit, the results match with an approximative solution of the Bethe ansatz (BA), suggesting crossover from a quasiparticle to a charge-density excitation regime.
- 1D lattice
- Ultracold Fermi gas