Related Experiment Video
Updated: Feb 15, 2026

Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Control of Ultracold Photodissociation with Magnetic Fields
M McDonald1, I Majewska2, C-H Lee1
1Department of Physics, Columbia University, 538 West 120th Street, New York, New York 10027-5255, USA.
Abstract:
Photodissociation of a molecule produces a spatial distribution of photofragments determined by the molecular structure and the characteristics of the dissociating light. Performing this basic reaction at ultracold temperatures allows its quantum mechanical features to dominate. In this regime, weak applied fields can be used to control the reaction. Here, we photodissociate ultracold diatomic strontium in magnetic fields below 10 G and observe striking changes in photofragment angular distributions. The observations are in excellent agreement with a multichannel quantum chemistry model that includes nonadiabatic effects and predicts strong mixing of partial waves in the photofragment energy continuum. The experiment is enabled by precise quantum-state control of the molecules.
Related Concept Videos
Magnetic Fields
A magnetic field is defined by the force that a charged particle experiences...
Magnetic Field of a Solenoid
Consider a solenoid with 100 turns wrapped around a cylinder of...
Magnetic Field Lines
Magnetic field lines follow several hard-and-fast rules:
Energy In A Magnetic Field
Take an ideal inductor with zero resistance. Although it's practically impossible, assume that the coil's resistance is so small that it is practically negligible. The loss of the field's energy to dissipate thermal energy (or heat) is thus...
Magnetic Field Of A Current Loop
Magnetic Field due to Moving Charges
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...

