Quantum soliton dynamics in vibrational chains: Comparison of fully correlated, mean field, and classical dynamics

The dynamics of a chain of vibrational bonds which develop a classical solitary compression wave is simulated. A converged fully correlated quantum mechanical calculation is compared with a time dependent mean field approach ~TDSCF! and with a classical simulation. The dynamics were all generated from the same Hamiltonian. The TDSCF and classical calculations show a fully developed solitary wave with the expected dependence of group velocity on amplitude. The full quantum calculations show a solitary-like wave which propagates for a while but then degrades. The robustness of the compression wave depends on the initial preparation. Evidence of partial recurrence of the wave has also been observed. © 2003 American Institute of Physics. @DOI: 10.1063/1.1555797#