Vibrationally Induced Two-Level Systems in Single-Molecule Junctions

Vibrationally induced two-level systems in single-molecule junctions.

Single-molecule junctions are found to show anomalous spikes in dI/dV spectra. The position in energy of the spikes is related to local vibration mode energies. A model of vibrationally induced two-level systems reproduces the data very well. This mechanism is expected to be quite general for single-molecule junctions. It acts as an intrinsic amplification mechanism for local vibration mode fea...

Experimental evidence for quantum interference and vibrationally induced decoherence in single-molecule junctions.

We analyze quantum interference and decoherence effects in single-molecule junctions both experimentally and theoretically by means of the mechanically controlled break junction technique and density-functional theory. We consider the case where interference is provided by overlapping quasidegenerate states. Decoherence mechanisms arising from electronic-vibrational coupling strongly affect the...

Numerically exact, time-dependent treatment of vibrationally coupled electron transport in single-molecule junctions.

The multilayer multiconfiguration time-dependent Hartree (ML-MCTDH) theory within second quantization representation of the Fock space, a novel numerically exact methodology to treat many-body quantum dynamics for systems containing identical particles, is applied to study the effect of vibrational motion on electron transport in a generic model for single-molecule junctions. The results demons...

Vibrationally mediated control of single-electron transmission in weakly coupled molecule-metal junctions

Plasmon-Induced Conductance Enhancement in Single-Molecule Junctions

The effect of surface plasmons on the conductance of singlemolecule junctions is studied using a squeezable break junction setup. We show that the conductance of 2,7-diaminofluorene single-molecule junctions can be enhanced upon laser irradiation. Our experimental approach enables us to show that this enhancement is due to the plasmon-induced oscillating field within the nanoscale metal gap of ...