AHARONOV-BOHM-TYPE EFFECT IN GRAPHENE TUBULES - A LANDAUER APPROACH

In this paper we show that (1) for graphene tubules an axial magnetic field can induce a semimetal-semiconductor transition periodically at zero bias. This is an Aharonov-Bohm-type effect and is generally true for thin cylindrical conductors; (2) the Landauer approach can be used to estimate the conductance of individual tubules measured by scannin g tunneling probes as a function of applied bias, temperature, tubule geometric factors, and magnetic field. Numerical calculations are pres ented showing that the conductance modulation should be observable eve n at room temperature.