Title: An ignition key for atomic-scale engines
Author(s): Dundas D., Cunningham B., Buchanan C., Terasawa A., Anthony T Paxton A.T., Todorov T.N.
Journal of Physics: Condensed Matter, 24, pp. 402203-1-402203-6 (2012)
A current-carrying resonant nanoscale device, simulated by non-adiabatic
molecular dynamics, exhibits sharp activation of non-conservative
current-induced forces with bias. The result, above the critical bias,
is generalized rotational atomic motion with a large gain in kinetic energy.
The activation exploits
sharp features in the electronic structure, and constitutes, in effect, an
ignition key for atomic-scale motors. A controlling factor for the effect
is the non-equilibrium dynamical response matrix for small-amplitude atomic motion
under current. This matrix can be found from the steady-state electronic structure
by a simpler static calculation, providing a way to detect the likely appearance, or
otherwise, of non-conservative dynamics, in advance of real-time modelling.