Universal trimers induced by spin-orbit coupling in ultracold Fermi gases.
In this Letter we address the issue of how synthetic spin-orbit (SO) coupling can strongly affect three-body physics in ultracold atomic gases. We consider a system which consists of three fermionic atoms, including two spinless heavy atoms and one spin-1/2 light atom subjected to an isotropic SO coupling. We find that SO coupling can induce universal three-body bound states with a negative s-wave scattering length at a smaller mass ratio, where no trimer bound state can exist if in the absence of SO coupling. The energies of these trimers are independent of the high-energy cutoff, and therefore they are universal ones. Moreover, the resulting atom-dimer resonance can be effectively controlled by SO coupling strength. Our results can be applied to systems like a 6Li and 40K mixture.
Institute for Advanced Study, Tsinghua University, Beijing 100084, China.
Zhe-Yu
ZY
Shi
Institute for Advanced Study, Tsinghua University, Beijing 100084, China and Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Xiaoling
X
Cui
Institute for Advanced Study, Tsinghua University, Beijing 100084, China.
Hui
H
Zhai