Correlated N-boson systems for arbitrary scattering length

TL;DR

This paper studies correlated N-boson systems with finite-range interactions, revealing universal scaling laws and the impact of correlations on condensate stability using a hyperspherical adiabatic approach.

Contribution

It introduces a hyperspherical adiabatic method with Faddeev decomposition to analyze correlations and universal scaling in bosonic condensates with arbitrary scattering length.

Findings

Universal scaling relations for effective radial potentials.

Correlations restore mean-field behavior at large distances.

Macroscopic tunneling dominates condensate decay under certain conditions.

Abstract

We investigate systems of identical bosons with the focus on two-body correlations and attractive finite-range potentials. We use a hyperspherical adiabatic method and apply a Faddeev type of decomposition of the wave function. We discuss the structure of a condensate as function of particle number and scattering length. We establish universal scaling relations for the critical effective radial potentials for distances where the average distance between particle pairs is larger than the interaction range. The correlations in the wave function restore the large distance mean-field behaviour with the correct two-body interaction. We discuss various processes limiting the stability of condensates. With correlations we confirm that macroscopic tunneling dominates when the trap length is about half of the particle number times the scattering length.