Quantum interference of electrons in multiwall carbon nanotubes

Abstract
In magnetoresistance measurements of a single multiwall carbon nanotube we have observed the periodic oscillation which increases in amplitude below 30 K. The period has the angular dependence of 1/cosθ, θ being the angle between the nanotube axis and magnetic field, and it corresponds to the field that the magnetic flux penetrating a nanotube equals one-third of a flux quanta, h/3e. The observation is explained in terms of the Aharonov-Bohm effect for three coexisting nanotubes with different chiralities.