Blowing the fuse: Berry's phase and runaway vibrations in molecular conductors.
We examine a molecular bridge connecting two metallic electrodes. We find that an electronic current passing across the bridge can cause a vibrational instability of the molecule, which ultimately can lead to a breakdown of the bridge. This instability is generated by a hitherto never considered mechanism, which surprisingly involves the quantum mechanical phase of the electronic waves, the "Berry phase". This mechanism works for highly conducting bridges, and contrary to breakdown by traditional Joule heating, this instability is deterministic and occurs at certain critical voltages. We demonstrate the new mechanism using state-of-the-art ab initio calculations on realistic molecular bridges.
Lü
Jing-Tao
JT
DTU Nanotech, Department of Micro and Nanotechnology, Technical University of Denmark, Ørsteds Plads, Building 345E, Kongens Lyngby, Denmark. jtlu@nanotech.dtu.dk
Brandbyge
Mads
M
Hedegård
Per
P
D003198:Computer Simulation; D004553:Electric Conductivity; D004579:Electron Transport; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D011789:Quantum Theory; D014732:Vibration