Polaron-molecule transitions in a two-dimensional Fermi gas
arXiv:1102.5534 · doi:10.1103/PhysRevA.83.051603
Abstract
We address the problem of a single "spin-down" impurity atom interacting attractively with a spin-up Fermi gas in two dimensions (2D). We consider the case where the mass of the impurity is greater than or equal to the mass of a spin-up fermion. Using a variational approach, we resolve the questions raised by previous studies and we show that there is, in fact, a transition between polaron and molecule (dimer) ground states in 2D. For the molecule state, we use a variational wave function with a single particle-hole excitation on the Fermi sea and we find that its energy matches that of the exact solution in the limit of infinite impurity mass. Thus, we expect the variational approach to provide a reliable tool for investigating 2D systems.
4 pages, 2 figures
References in corpus (13)
- Observation of Fermi Polarons in a Tunable Fermi Liquid of Ultracold Atoms
- Phase diagram of a two-component Fermi gas with resonant interactions
- Fermi-Polaron: Diagrammatic Monte Carlo for Divergent Sign-Alternating Series
- Deformation of a Trapped Fermi Gas with Unequal Spin Populations
- Radiofrequency spectroscopy of a strongly interacting two-dimensional Fermi gas
- Observation of a two-dimensional Fermi gas of atoms
- Normal state of highly polarized Fermi gases: Full many-body treatment
- Trimers, molecules and polarons in imbalanced atomic Fermi gases
- Ground state of a tightly bound composite dimer immersed in a Fermi Sea
- Polarons and Molecules in a Two-Dimensional Fermi Gas
- Decay of polarons and molecules in a strongly polarized Fermi gas
- Superfluidity at the BEC-BCS crossover in two-dimensional Fermi gases with population and mass imbalance
- Highly polarized Fermi gases: One-dimensional case