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arXiv · 0902.2854

Pseudo-potential of a power-law decaying interaction in two-dimensional systems

Abstract

We analytically derive the general pseudo-potential operator of an arbitrary isotropic interaction for particles confined in two-dimensional (2D) systems, using the frame work developed by Huang and Yang for 3D scattering. We also analytically derive the low energy dependence of the scattering phase-shift for an arbitrary interaction with a power-law decaying tail, $V_{\rm 2D}(ρ)\propto ρ^{-α}$ (for $α>2$). We apply our results to the 2D dipolar gases ($α=3$) 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. Results for the s-wave scattering between particles in two different (parallel) layers are also investigated. Our results can be directly applied to the systems of dipolar atoms and/or polar molecules in a general 2D geometry.

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Sheng-Min Shih, Daw-Wei Wang. 2009-04-17. Pseudo-potential of a power-law decaying interaction in two-dimensional systems. https://doi.org/10.1103/physreva.79.065603

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