A quasi-static treatment of multiple phase jumps
R. Englman, Tamás Vértesi
A quasi-static, WKB-type treatment accounts well for the surprising phase jumps that are odd multiples of π, (1 + 2 n )π, found as a molecular system journeys adiabatically in a configuration coordinate plane that contains several points of degeneracies. We show that the number n in the phase jump is an integer close to | n '| that appears in the expression for the complex wavefunction amplitude valid (approximately) for times close to when the phase jump occurs: (δ T is a shifted and rescaled trajectory-time parameter and θ is a numerical fraction (<1) which depends on the adiabaticity of the motion.) The central quantity n ' is local, i.e., depends on the values of the parameters in the Hamiltonian only at the beginning of the trajectory and at the instant of the phase jump.
Journal of Physics B Atomic Molecular and Optical Physics•Jun 27, 2005•10 citations