Dustin Fisher with Harsh Mathur

Phantom Interference Effects in Quantum Tunneling

It has recently been observed [1, 2] that radioactive decay of certain isotopes [Praesodymium-140 (140Pr) and Promethium-142 (142Pm)] exhibit an oscillatory exponential time dependence in a marked departure from the simple exponential behavior that is normally observed. A recent theoretical study [3] of electrons tunneling off the surface of liquid helium predicted that electronic tunneling decay could show oscillatory exponential behavior due to quantum interference between the decaying electronic state and a nearby unoccupied “phantom” state. This mechanism is quite general and should also apply to other quantum systems including atomic nuclei. The purpose of this project is to adapt the theory of ref [3] to the problem of nuclear beta decay via K-capture and to determine whether it can account for the oscillations observed by ref [1].

[1] Litvinov, Yu. A. et al. Phys. Lett. B 644, 162-168 (2008)
[2] Walker, Philip M. Nature 453, 864-865 (12 June 2008)
[3] S. Duki and H. Mathur arXiv:0804.2210v1, (14 April 2008)