project title: Feedback mechanism in single-electron tunneling devices
project leader: Yaroslav Blanter
access given (in days): 14
access used (in days): 6
local host: Pertti Hakonen
home institution: Delft University of Technology
country of institution: The Netherlands
starting date (yyyy-mm-dd): 2006-03-26
A harmonic nanomechanical oscillator with a high quality factor, weakly coupled to a single-electron tunneling device, can provide a strong feedback for electron transport. Strong feedback occurs in a narrow voltage range just above the Coulomb blockade threshold. In this regime, current is strongly modified and current noise is drastically enhanced compared to the Schottky value. In this project, we will investigate, how such a feedback mechanism could be taken into account in the design of an ultrasensitive mass-sensor based on oscillation of a freestanding carbon nanotube.
The feedback mechanism from mechanical motion back to single electron tunneling has been considered in carbon nanotube resonators. The feedback mechanism will affect, among other things, shot noise of electron tunneling. The feasibility of investigating this feedback effect using shot noise measurements at GHz frequencies has been considered. The conclusion was that the sensitivity of the present shot noise measurements has to be enhanced before such measurements are feasible.