Sunlight could cool an atom to its coldest possible temperature

Sunlight could be used to cool a charged atom to its lowest temperature allowed by the legal guidelines of physics.

In the Nineties, a number of folks gained Nobel prizes for understanding how to make atoms extraordinarily chilly with exactly managed laser gentle. Now, Amanda Younes and Wesley Campbell on the University of California, Los Angeles, have discovered that some components of the cooling course of could be completed with gentle straight from the solar.

The researchers calculated how a single positively charged barium atom, or ion, …