
Laser Brakes for Potassium and Cesium: A Mix That Had Never Been Made
Two cars of different masses roll down the same track, and a laser beam acts as a common brake that slows both to a pedestrian's pace. That's exactly how physicists from the University of Warsaw for the first time stopped and held together atoms of potassium-41 and cesium, a mixture that no one had been able to catch in a light trap before.