Physics – Condensed Matter – Mesoscale and Nanoscale Physics
Scientific paper
2011-07-29
Physics
Condensed Matter
Mesoscale and Nanoscale Physics
21 pages, 8 figures
Scientific paper
The transport through a quantum-scale device may be characterized by the transmission eigenvalues. These values constitute a junction PIN code where, for example, in single-atom metallic contacts the number of transmission channels is also the chemical valence of the atom. Recently, highly conductive single-molecule junctions (SMJ) with multiple transport channels have been formed from benzene molecules between Pt electrodes. Transport through these multi-channel SMJs is a probe of both the bonding properties at the lead-molecule interface and of the molecular symmetry. Here we utilize a many-body theory that properly describes the complementary nature of the charge carrier to calculate transport distributions through Pt-benzene-Pt junctions. We develop an effective field theory of interacting pi-electrons to accurately model the electrostatic influence of the leads and an ab initio tunneling model to describe the lead-molecule bonding. With this state-of-the-art many-body technique we calculate the transport using the full molecular spectrum and using an `isolated resonance approximation' for the molecular Green's function. We confirm that the number of transmission channels in a SMJ is equal to the degeneracy of the relevant molecular orbital. In addition, we demonstrate that the isolated resonance approximation is extremely accurate and determine that transport occurs predominantly via the HOMO orbital in Pt-benzene-Pt junctions. Finally, we show that the transport occurs in a lead-molecule coupling regime where the charge carriers are both particle-like and wave-like simultaneously, requiring a many-body description.
Barr Joshua D.
Bergfield Justin P.
Stafford Charles A.
No associations
LandOfFree
Transmission eigenvalue distributions in highly-conductive molecular junctions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Transmission eigenvalue distributions in highly-conductive molecular junctions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transmission eigenvalue distributions in highly-conductive molecular junctions will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-318281