Validity of time-dependent trial states for the Holstein polaron

Validity of three time-dependent trial states of the Holstein Hamiltonian, namely the D-2, Merrifield and (D) over tilde Ansatze has been examined in detail with regards to their deviations from the exact solution to the time-dependent Schrodinger equation. Linear absorption spectra are also calculated as an additional indicator of the Ansatz validity. It is found that the (D) over tilde Ansatz is the most accurate trial state of the three, and all Ansatze fail to provide an adequate description of system dynamics in the weak-coupling regime.