Photoconductance of organic single-molecule contacts

Abstract

We study the dc conductance of organic single-molecule contacts in the presence of external electromagnetic radiation (photoconductance). In agreement with previous predictions, we find that the radiation can lead to large enhancements of the conductance of such contacts by bringing off-resonant levels into resonance through photoassisted processes. In our analysis we make use of the simplifying fact that, under certain assumptions, the photoconductance can be expressed in terms of the transmission function in the absence of the radiation. The conductance enhancement is demonstrated for oligophenylene molecules between gold electrodes, whose electronic structure is calculated based on density-functional theory. It is shown that the exponential decay of the conductance with the length of the molecule can be replaced by a length-independent value in the presence of radiation.

4 pages, 2 figures

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Cited by in corpus (9)

• Length-dependent conductance and thermopower in single-molecule junctions of dithiolated oligophenylene derivatives
• Tilt-angle landscapes and temperature dependence of the conductance in biphenyl-dithiol single-molecule junctions
• Cluster-based density-functional approach to quantum transport through molecular and atomic contacts
• Modeling elastic and photoassisted transport in organic molecular wires: length dependence and current-voltage characteristics
• Electronic and optical properties of electromigrated molecular junctions
• Linear optical response of current-carrying molecular junction: A NEGF-TDDFT approach
• Light-induced current in molecular junctions: Local field and non-Markov effects
• Molecular nanoplasmonics: self-consistent electrodynamics in current carrying junctions
• Conductance through analytic constrictions