Determination of the Intershell Conductance in Multiwalled Carbon Nanotubes

We report on the intershell electron transport in multiwalled carbon nanotubes (MWNT). To do this, local and nonlocal four-point measurements are used to study the current path through the different shells of a MWNT. For short electrode separations $\lesssim$ 1 $\mu$m the current mainly flows through the two outer shells, described by a resistive transmission line with an intershell conductance per length of ~(10 k\Omega)^{-1}/$\mu$m. The intershell transport is tunnel-type and the transmission is consistent with the estimate based on the overlap between $\pi$-orbitals of neighboring shells.