Ensemble averaging of conductance fluctuations in multiwall carbon nanotubes

Abstract

We report resistance measurements for a single multiwall carbon nanotube as a function of gate voltage and perpendicular magnetic field. The tubes were trapped onto pre-patterned Al electrodes by means of an ac electric field. Magnetoresistance traces measured for various values of the gate voltage were averaged, which corresponds to an ensemble averaging of conductance fluctuations induced by quantum interference. The ensemble averaging decreases the conductance fluctuations, while leaving the weak localization contribution to the resistance unchanged. Our data can be consistently interpreted in terms quantum transport in the presence of a weak disorder.