Momentum-resolved radio-frequency spectroscopy of a spin-orbit coupled atomic Fermi gas near a Feshbach resonance in harmonic traps

We theoretically investigate the momentum-resolved radio-frequency spectroscopy of a harmonically trapped atomic Fermi gas near a Feshbach resonance in the presence of equal Rashba and Dresselhaus spin-orbit coupling. The system is qualitatively modeled as an ideal gas mixture of atoms and molecules, in which the properties of molecules, such as the wavefunction, binding energy and effective mass, are determined from the two-particle solution of two-interacting atoms. We calculate separately the radio-frequency response from atoms and molecules at finite temperatures by using the standard Fermi golden rule, and take into account the effect of harmonic traps within local density approximation. The total radio-frequency spectroscopy is discussed, as functions of temperature and spin-orbit coupling strength. Our results give a qualitative picture of radio-frequency spectroscopy of a resonantly interacting spin-orbit coupled Fermi gas and can be directly tested in atomic Fermi gases of K40 atoms at Shanxi University and of Li6 atoms at MIT.Comment: 11 pages, 9 Figure

Two-channel model description of confinement-induced Feshbach molecules

Using a two-channel model, we investigate theoretically the binding energy of confinement-induced Feshbach molecules in two- and one-dimensional ultracold atomic systems, near a Feshbach resonance. We show that the two-channel prediction will evidently deviate from the simple single-channel theory as the width of Feshbach resonances decreases. For one-dimensional system, we perform a full two-channel calculation, with the inclusion of bare interatomic interactions in the open channel. Away from the resonance, we find a sizable correction to the binding energy, if we neglect incorrectly the bare interatomic interactions as in the previous work [Dickerscheid and Stoof, Phys. Rev. A 72, 053625 (2005)]. We compare our theoretical results with existing experimental data and present predictions for narrow Feshbach resonances that could be tested in future experiments.Comment: 8 pages, 5 figure