Two interacting ultracold molecules in a one-dimensional harmonic trap

TL;DR

This paper models two ultracold polar molecules in a 1D harmonic trap, analyzing their energy spectra considering anisotropic interactions and external fields, with implications for quantum simulation.

Contribution

It introduces a detailed theoretical model of two interacting ultracold molecules in a harmonic trap, including anisotropic interactions and external field effects, advancing molecular quantum simulation research.

Findings

Energy spectra and eigenstates calculated via exact diagonalization.

Analysis of the interplay between rotational structure, interactions, and external fields.

Comparison with two trapped atoms highlights molecular-specific effects.

Abstract

We investigate the properties of two interacting ultracold polar molecules described as distinguishable quantum rigid rotors, trapped in a one-dimensional harmonic potential. The molecules interact via a multichannel two-body contact potential, incorporating the short-range anisotropy of intermolecular interactions including dipole-dipole interaction. The impact of external electric and magnetic fields resulting in Stark and Zeeman shifts of molecular rovibrational states is also investigated. Energy spectra and eigenstates are calculated by means of the exact diagonalization. The importance and interplay of the molecular rotational structure, anisotropic interactions, spin-rotation coupling, electric and magnetic fields, and harmonic trapping potential are examined in detail, and compared to the system of two harmonically trapped distinguishable atoms. Presented model and results may provide microscopic parameters for molecular many-body Hamiltonians, and may be useful for the development of bottom-up molecule-by-molecule assembled molecular quantum simulators.