Atom--Molecule Coherence in a Bose-Einstein Condensate

TL;DR

This paper reports the observation of coherent atom-molecule coupling in a Bose-Einstein condensate, demonstrating quantum superposition and oscillations between atomic and molecular states near a Feshbach resonance.

Contribution

It provides the first experimental evidence of coherent atom-molecule oscillations in a BEC and measures their frequency across various magnetic fields.

Findings

Oscillations between atomic and molecular states observed.

Oscillation frequency matches energy difference predictions.

Quantum superposition of atoms and molecules demonstrated.

Abstract

Coherent coupling between atoms and molecules in a Bose-Einstein condensate (BEC) has been observed. Oscillations between atomic and molecular states were excited by sudden changes in the magnetic field near a Feshbach resonance and persisted for many periods of the oscillation. The oscillation frequency was measured over a large range of magnetic fields and is in excellent quantitative agreement with the energy difference between the colliding atom threshold energy and the energy of the bound molecular state. This agreement indicates that we have created a quantum superposition of atoms and diatomic molecules, which are chemically different species.