Two atoms in a harmonic trap with spin-orbital-angular-momentum coupling

TL;DR

This paper investigates the energy spectrum and correlations of two atoms in a harmonic trap with spin-orbital-angular-momentum coupling, revealing how interactions and coupling influence degeneracy and correlations.

Contribution

It provides the first detailed numerical analysis of two-atom systems with SOAM coupling, comparing results with perturbation theory and discussing correlation properties.

Findings

Energy level degeneracy is lifted by SOAM coupling and interactions.

Numerical results agree with perturbation theory in weak interaction and no SOAM coupling limits.

Analysis of atomic correlations as a function of interaction strength.

Abstract

We study the problem of two harmonically trapped atoms in the presence of spin-orbital-angular-momentum (SOAM) coupling. The two-body energy spectrum is numerically calculated by utilizing the exact diagonalization method. We analyze how the degeneracy of energy levels is lifted under the interplay between the interatomic interaction and SOAM coupling. The exact numerical results show excellent agreement with that of perturbation theory in the weak-interaction limit as well as that in the absence of SOAM coupling. The properties of correlations between the two atoms are also discussed with respect to the interaction strength. The findings in this paper may provide valuable insights into few-body physics subjected to SOAM coupling and the possible experimental detection of spectrum functions in many-body systems, such as radiofrequency spectroscopy.