Trapped and chilled

Laser cooling and magneto-optical trapping have been used to hold and chill strontium monofluoride to within 2.5 thousandths of a degree absolute zero. Details are published in the journal Nature and team member Dave DeMille of Yale University says, “We can now start studying chemical reactions that are happening at very near to absolute zero." He adds that, “We have a chance to learn about fundamental chemical mechanisms.” Until recently magneto-optical trapping was only available to holding single atoms for study. The team developed their own custom-built apparatus that uses a dozen lasers each tuned with 10 significant figures of precision