Pseudo-potential of an arbitrary isotropic interaction in two-dimensional systems
Sheng-Ming Shih, Daw-Wei Wang
Abstract
We analytically derive the general pseudo-potential operator of an arbitrary isotropic interaction for particles confined in two-dimensional (2D) systems, using the same frame work developed by Huang and Yang for 3D scattering [Phys. Rev. {\bf 105}, 767 (1957)]. We also analytically derive the low energy dependence of the phase-shift for an arbitrary potential with a power-law decaying tail, $V_{\rm 2D}(\rho)\propto \rho^{-\alpha}$ (for $\alpha>2$). We apply our results to the 2D dipolar gases ($\alpha=3$) as an example, calculating the momentum and dipole moment dependence of the pseudo-potential for both $s$- and p-wave scattering channels if the two scattering particles are in the same 2D layer. We also calculate the result for the s-wave scattering between particles in two different (parallel) layers. Our analytic and numerical results can be directly applied to the study of many-body properties of magnetic dipolar atoms and/or polar molecules in a general 2D system.