1212.5696 (Dirk Hofmann et al.)

Measuring excitation-energy transfer with a real-time time-dependent
density functional theory approach    [PDF]

Dirk Hofmann, Heiko Appel, Massimiliano Di Ventra, Stephan Kümmel

We investigate the time an electronic excitation travels in a supermolecular setup using a measurement process in an open quantum-system framework. The approach is based on the stochastic Schr\"odinger equation and uses a Hamiltonian from time-dependent density functional theory (TDDFT). It treats electronic-structure properties and intermolecular coupling on the level of TDDFT, while it opens a route to the description of dissipation and relaxation via a bath operator that couples to the dipole moment of the density. Within our study, we find that in supermolecular setups small deviations of the electronic structure from the perfectly resonant case have only minor influence on the pathways of excitation-energy transfer, thus lead to similar transfer times. Yet, sizable defects cause notable slowdown of the energy spread.

View original: http://arxiv.org/abs/1212.5696