Vibrational effects in laser-driven molecular wires.

نویسندگان

  • Jörg Lehmann
  • Sigmund Kohler
  • Volkhard May
  • Peter Hänggi
چکیده

The influence of an electron-vibrational coupling on the laser control of electron transport through a molecular wire that is attached to several electronic leads is investigated. These molecular vibrational modes induce an effective electron-electron interaction. In the regime where the wire electrons couple weakly to both the external leads and the vibrational modes, we derive within a Hartree-Fock approximation a nonlinear set of quantum kinetic equations. The quantum kinetic theory is then used to evaluate the laser driven, time-averaged electron current through the wire-leads contacts. This formalism is applied to two archetypical situations in the presence of electron-vibrational effects, namely, (i) the generation of a ratchet or pump current in a symmetrical molecule by a harmonic mixing field and (ii) the laser switching of the current through the molecule.

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عنوان ژورنال:
  • The Journal of chemical physics

دوره 121 5  شماره 

صفحات  -

تاریخ انتشار 2004