Experimental evidence for non-exponential decay in quantum tunnelling

@article{Wilkinson1997ExperimentalEF,
  title={Experimental evidence for non-exponential decay in quantum tunnelling},
  author={Steven R. Wilkinson and C. F. Bharucha and Martin C. Fischer and Kirk W. Madison and P. R. Morrow and Q. Niu and Bala Sundaram and Mark Raizen},
  journal={Nature},
  year={1997},
  volume={387},
  pages={575-577}
}
An exponential decay law is the universal hallmark of unstable systems and is observed in all fields of science. This law is not, however, fully consistent with quantum mechanics and deviations from exponential decay have been predicted for short as well as long times. Such deviations have not hitherto been observed experimentally. Here we present experimental evidence for short-time deviation from exponential decay in a quantum tunnelling experiment. Our system consists of ultra-cold sodium… 

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