화학공학소재연구정보센터
Journal of Physical Chemistry B, Vol.110, No.38, 18758-18763, 2006
Condensed-phase relaxation of multilevel quantum systems. I. An exactly solvable model
An analytically solvable model of multilevel condensed-phase quantum dynamics relevant to vibrational relaxation and electron transfer is presented. Exact solutions are derived for the reduced system density matrix dynamics of a degenerate N-level quantum system characterized by nearest-neighbor hopping and off-diagonal coupling ( which is linear in the bath coordinates) to a harmonic oscillator bath. We demonstrate that for N > 2 the long-time steady-state system site occupation probabilities are not the same for all sites; that is, they are distributed in a non-Boltzmann manner, which depends on the initial conditions and the number of levels in the system. Although the system-bath Hamiltonian considered here is restricted in form, the availability of an exact solution enables us to study the model in all regions of an extensive parameter space.