Laser-induced currents along molecular wire junctions

Abstract

The treatment of the previous paper is extended to molecular wires. Specifically, the effect of electron-vibrational interactions on the electronic transport induced by femtosecond $\omega +2\omega$ laser fields along unbiased molecular nanojunctions is investigated. For this, the photoinduced vibronic dynamics of trans-polyacetylene oligomers coupled to macroscopic metallic leads is followed in a mean-field mixed quantum-classical approximation. A reduced description of the dynamics is obtained by introducing projective lead-molecule couplings and deriving an effective Schrödinger equation satisfied by the orbitals in the molecular region. Two possible rectification mechanisms are identified and investigated. The first one relies on near-resonance photon-absorption and is shown to be fragile to the ultrafast electronic decoherence processes introduced by the wire's vibrations. The second one employs the dynamic Stark effect and is demonstrated to be highly efficient and robust to electron-vibrational interactions.

14 pages, 10 figures. Accepted in J. Chem. Phys

References in corpus (8)

• Current induced light emission and light induced current in molecular tunneling junctions
• The influence of ultra-fast laser pulses on electron transfer in molecular wires studied by a non-Markovian density matrix approach
• Inelastic tunneling effects on noise properties of molecular junctions
• Optical properties of current carrying molecular wires
• Vibrational effects in laser driven molecular wires
• Rectification of laser-induced electronic transport through molecules
• Robust ultrafast currents in molecular wires through Stark shifts
• Femtosecond dynamics and laser control of charge transport in trans-polyacetylene