Levinson's theorem for time-periodic potentials
Institut de Physique Théorique, Ecole Polytechnique
Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
Accepted: 7 May 1996
Levinson's theorem is generalized to quantum scattering with time-periodic potentials. The zero-energy limit of the phase shift in the elastic channel is linked to the number of bound (cyclic) states of the time-dependent potential by the same relation as in the static case.
PACS: 03.65.Nk – Nonrelativistic scattering theory / 03.65.Ge – Solutions of wave equations: bound states
© EDP Sciences, 1996