Decay and Recurrences of Wave Packets in Nonlinear Quantum Systems
A simple and analytical model of quantum recurrences in wave packet dynamics of nonlinear vibrational systems is presented. It is shown that in addition to "normal" rephasing time τR the width of the packet experiences very strong recurrences at τR/2. In a quasiclassical limit, which can be studied explicitly in this model, the recurrences disappear and the decay becomes irreversible. Recent femtosecond experimental results of Zewail and co-workers are discussed in the framework of this analytical model.
© 1994 American Chemical Society. Received: August 31, 1993; In Final Form: October 27, 1993. It is a great pleasure to dedicate this paper to our friend and colleague, Joshua Jortner, on the occasion of his sixtieth birthday. We would like to acknowledge the discussion of results of this paper with Kevin Lehmann and Ahmed Zewail. The financial support of the National Science Foundation is also greatly acknowledged. This work is part of the Caltech-JPL Supercomputing Project Collaboration.