Treatment of laser-field effects on a molecular wire and its coupling to the leads

The influence of strong laser pulses on molecular wires is studied within different theoretical approaches. The wire is modeled by a tight-binding system coupled to two fermionic reservoirs mimicking the electronic leads. In the present model the effect of the laser field is two-fold: it directly influences the site energies but also modulates the coupling between wire and leads. In this investigation we study the effects of two approximations on treating the indirect field effect. The results from the approximative treatment are compared to a theory which takes fully into account the laser-field effect on the coupling term. (C) 2007 Elsevier B.V. All rights reserved.