Accelerating Particles with the Brightest Lasers on Earth

What happens when you focus one of the world's most powerful lasers on a spot so tiny it can be hidden by a human hair? Using the J-KAREN-P laser at the Kansai Photon Science Institute (KPSI) in Japan, a team led by researchers from the National Institutes for Quantum and Radiological Science and Technology (QST) in Japan investigated this extreme situation. As they report in the American Physical Society's journal Physical Review Letters, the experimental results reveal a fundamental limit that...