Father time: the physicist on a mission to build the world's first nuclear clock

"We thought we could very quickly do a kind of demonstration experiment," says Peik. For more than a year, they tried different ways to nudge nuclei of radioactive thorium-229 into an excited state. Then they would need to tune a laser to the energy of the nuclei's transition and eventually use its frequency to mark time. "But the experiments all failed," he says."

"Now everybody wants a piece," says Thorsten Schumm, an atomic physicist and Peik's collaborator at the Vienna University of Technology. Peik’s perseverance paid off this year when his was the first of three groups to excite the nucleus to make it 'tick'."

Read at Nature