Electrical transport in single-walled carbon nanotube bundles embedded in Langmuir–Blodgett monolayers

Langmuir films consisting of single-walled carbon nanotubes and surfactant molecules were deposited on substrates with lithographically defined electrode arrays. Atomic force microscopy revealed a different matrix structure of the Langmuir–Blodgett monolayers compared to monolayers on bare substrates. Electrical transport measurements were performed on individual thin bundles at room temperature and 4.2 K. At low temperatures, the current/voltage characteristics show a non-linear dependence with step-like features, which are critically discussed in the frame of Coulomb charging theory and electron tunneling through discrete energy levels.