Large Effects of Electric Fields on Atom-Molecule Collisions at Millikelvin Temperatures

TL;DR

This paper demonstrates that electric fields significantly influence atom-molecule collisions at millikelvin temperatures, revealing new quantum effects and collision dynamics in ultracold systems.

Contribution

It introduces a novel experimental setup combining magnetic and electric trapping to study ultracold atom-molecule collisions under external fields, highlighting electric field effects beyond dipole interactions.

Findings

Electric fields alter collision outcomes at ultracold temperatures.

Inelastic collision rates increase under applied electric fields.

Quantum scattering calculations confirm electric field influence without dipole-dipole interactions.

Abstract

Controlling interactions between cold molecules using external fields can elucidate the role of quantum mechanics in molecular collisions. We create a new experimental platform in which ultracold rubidium atoms and cold ammonia molecules are separately trapped by magnetic and electric fields and then combined to study collisions. We observe inelastic processes that are faster than expected from earlier field-free calculations. We use quantum scattering calculations to show that electric fields can have a major effect on collision outcomes, even in the absence of dipole-dipole interactions.