Quantum interference in carbon nanotube electron resonators

The quantum conductance fluctuations of the electron resonator composed of the single-walled carbon nanotube (SWNT) has been studied numerically. It is shown that the conductance oscillations appear at the strong coupling between the electrical contact and SWNT, and become well-defined resonant peaks as the coupling is very weak. It is also found that the disorder and defects in the SWNT cannot induce the observed slow and fast conductance oscillations. More importantly, it is demonstrated that the experimentally observed deep dip in the conductance G vs Fermi-energy plot is probably caused by the chemisorbed atoms on the SWNT.