Pseudopotential for the 2D contact interaction

TL;DR

This paper introduces a new smooth pseudopotential for 2D ultracold atom interactions that significantly improves accuracy in scattering property reproduction and accelerates Monte Carlo simulations.

Contribution

The authors develop a pseudopotential that outperforms existing models in accuracy and computational efficiency for 2D contact interactions.

Findings

Reproduces scattering properties up to 200 times more accurately than hard disk potential.

Provides a 10-fold accuracy improvement over square well potential in the attractive branch.

Enables diffusion Monte Carlo simulations to run 15 times faster.

Abstract

We propose a smooth pseudopotential for the contact interaction acting between ultracold atoms confined to two dimensions. The pseudopotential reproduces the scattering properties of the repulsive contact interaction up to 200 times more accurately than a hard disk potential, and in the attractive branch gives a 10-fold improvement in accuracy over the square well potential. Furthermore, the new potential enables diffusion Monte Carlo simulations of the ultracold gas to be run 15 times quicker than was previously possible.