In this paper we consider quantum metastability in a class of moving potentials introduced by Berry and Klein. This class of potential has height and width scaled in a specific way so that it can be transformed into a stationary one. While deriving the nondecay probability of the system, we demonstrate that the appropriate technique to use is the less well known method of scattering states. This method is illustrated through two examples, namely, a moving δ-function potential and a moving barrier potential. For expanding potentials, one finds that a small but finite nondecay probability persists at large times. Generalization to scaling potentials of arbitrary shape is briefly outlined.
Physical Review A (Atomic, Molecular, and Optical Physics) 65(2), 022111(8pages)