Rubidium atoms’ tunnelling time measured with quantum stopwatch
By 
Katrina Krämer2020-07-30T08:30:00
Ultracold atom’s time inside forbidden barrier determined, but experiment might not resolve the controversy surrounding tunnelling time
By putting a 50-year-old thought experiment about a quantum clock into practice, physicists have for the first time measured how long rubidium atoms spend inside the ‘forbidden’ barrier region during quantum tunnelling – 0.6ms. The work aims to address the controversy surrounding tunnelling time, which has seen some studies proposing finite times while others suggest the process is instantaneous.