Electronic mean free path in as-produced and purified single-wall carbon nanotubes

Abstract

The effect of purification on room temperature electronic transport properties of singlewall carbon nanotubes (SWNT) was studied by submerging samples into liquid mercury.The conductance plots of purified SWNTs showed plateaus, indicating weak dependence of the electrical resistance on the length of the tube connecting the electrodes, providing evidence of quasi-ballistic conduction in SWNTs. The electronic mean free path of the purified SWNTs reached a few microns, which is longer than that of the as-produced SWNTs, and which is consistent with the calculation based on the scattering by acoustic phonons.

Charge Transport in Interpenetrating Networks of Semiconducting and Metallic Carbon Nanotubes

“…The length (L) and density (n) range of tubes was chosen to match the devices investigated experimentally in Figure 1 (L ) 4 µm, n ) 2 µm CNT /µm 2 or 0.5 tubes/µm 2 ). Tube resistance was measured using scanned potentiometry (see Supporting Information) to be R tube ) 13 kΩ/µm, similar to values found in literature, 14,29,[43][44][45][46] and tube junction resistance, R junction ) 200 kΩ/junction, was taken from literature. 20 We begin with a simplifying set of assumptions that, given ambient p-type O 2 doping and for V g ) 0 V, all nanotubes in the film have similar electrical properties.…”

Ballistic- and quantum-conductor carbon nanotubes: A reference experiment put to the test

“…According to the criteria suggested in the original work of Frank et al [18] and subsequently accepted in the literature [19,[22][23][24][25][26], the same experimental results (if acquired in an ex situ experiment without visual control) would show that the CNT at the apex of the tip is a ballistic conductor (due to the stability of the plateaus) and that its conductance is quantified (due to the appearance of peaks in the histogram). One can therefore define a quantification step G 1 which is the conductance value of which the total measured conductance appears to always be an integer multiple.…”

“…This experiment was performed by using an elegant liquid-metal contact method (LMC method) consisting of immersing the MWNTs placed on the apex of a metallic tip into a liquid metal [usually mercury (Hg)] and by supposing that in this way a mobile contact on the MWNT would be created [see Fig. 1 This experiment has incited much similar work by several other groups [19,[22][23][24][25][26] who considered the LMC method (or similar methods consisting of a cyclic immersion with no simultaneous visualization) also applicable on thin CNTs with micrometric lengths, i.e., single-wall CNTs (SWNTs) [23,25,26], double-wall CNTs (DWNTs) [22], and MWNTs [19,24] with a small number of walls. The interest of this kind of CNTs lies in their micrometric length which allows one to test micrometric EMFPs and in their limited wall number which facilitates the study of interwall interactions as well as in the unambiguous identification of their chiral indices by electron diffraction [27].…”

Algebraic Current-voltage and Voltage Dependent Resistance Expressions for Ballistic Nano Conductors and Their Low Voltage Nonlinearity

“…It is worth noting that the mean free path in metallic carbon nanotubes are measured as 1.5 µm [16] while the mean free path of electrons in GNRs and gold nanowires are given as 100 nm and 50 nm, respectively [17,18]. Considering the expected interconnect lengths in the ITRS roadmap [19], nano interconnects can be used in the ballistic regime.…”