Interatomic collisions in two-dimensional and quasi-two-dimensional confinements with spin-orbit coupling

We investigate the low-energy scattering and bound states of two two-component fermionic atoms in pure two-dimensional (2D) and quasi-2D confinements with Rashba spin-orbit coupling (SOC). We find that the SOC qualitatively changes the behavior of the 2D scattering amplitude in the low-energy limit. For quasi-2D systems we obtain the analytic expression for the effective 2D scattering amplitude and the algebraic equations for the two-atom bound-state energy. We further derive the effective 2D contact potential for the interaction between ultracold atoms in the quasi-2D confinement. This effective potential can be used in the research on many-body physics of quasi-2D ultracold Fermi gases with Rashba SOC.