2007/04/03 by J. K. Viljas, Fabian Pauly, F. Pauly +2
Chemistry · Engineering · Physics and Astronomy · #Atomic physics #Chemical physics #Chemistry #Computational chemistry #Condensed matter physics #Conductance #Density functional theory #Electrode #Force Microscopy Techniques and Applications #Materials science #Mechanical and Optical Resonators #Molecular Junctions and Nanostructures #Molecular physics #Molecule #Nanotechnology #Optics #Optoelectronics #Physical chemistry #Physics #Radiation #Resonance (particle physics) #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.76.033403
published as Phys. Rev. B 76, 033403 (2007) · 4 pages, 2 figures
arxiv created 2007/04/03 · openalex publication_date 2007/07/02 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
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.