Ultracold Molecule Production Via a Resonant Oscillating Magnetic Field

TL;DR

This paper presents a new method for converting ultracold atoms into molecules using a resonant oscillating magnetic field, enabling high efficiency and precise spectroscopy without crossing the Feshbach resonance.

Contribution

It introduces a novel atom-molecule conversion technique using a sinusoidal magnetic field modulation near a Feshbach resonance, improving efficiency and spectroscopic capabilities.

Findings

Conversion efficiency depends on frequency, amplitude, and duration of modulation.

High conversion efficiencies achieved without crossing the Feshbach resonance.

Technique enables precise spectroscopic measurements.

Abstract

A novel atom-molecule conversion technique has been investigated. Ultracold 85Rb atoms sitting in a DC magnetic field near the 155G Feshbach resonance are associated by applying a small sinusoidal oscillation to the magnetic field. There is resonant atom to molecule conversion when the modulation frequency closely matches the molecular binding energy. We observe that the atom to molecule conversion efficiency depends strongly on the frequency, amplitude, and duration of the applied modulation and on the initial phase space density of the sample. This technique offers high conversion efficiencies without the necessity of crossing or closely approaching the Feshbach resonance and allows precise spectroscopic measurements.