Geometrical Dependence of High-Bias Current in Multiwalled Carbon Nanotubes

Abstract

We have studied the high-bias transport properties of the different shells that constitute a multiwalled carbon nanotube. The current is shown to be reduced as the shell diameter is decreased or the length is increased. We assign this geometrical dependence to the competition between the electron-phonon scattering process and Zener tunneling.

Electrical characteristics of multiwalled carbon nanotube arrays and influence of pressure

“…Similar results have also been observed for individual NTs. 4,11,13 The rapid increase of current with voltage has also been observed for experiments performed at different pressures (10 -6 Torr range) as shown in Figs. 2(b)-2(d).…”

“…1 Remarkable is that the current saturation have been observed for metallic as well as semiconducting single-walled NT (SWNT), [1][2][3][4][5][6][7][8] which is attributed to the electron back scattering by high energy phonon, 3 and interband zener tunneling. 11 However, a series of independent transport measurements on various length demonstrated the absence of current saturation in NTs shorter than 55 nm. 9,10 The mean free path of optical phonon scattering is in the range of 10-100 nm and therefore, the absence of current saturation was interpreted as ballistic transport along the NTs.…”

“…Over the last decade, transport properties have been studied extensively for NTs of length between 10 nm and 11 μm. [1][2][3][4][5][6][7][8][9][10][11][12] The current-voltage (IV) characteristics of individual metallic NTs are shown to be dependent not only on diameter and length, [1][2][3][4][5][6][7][8][9][10][11][12] but also on the substrate-NTs interaction. 1 Remarkable is that the current saturation have been observed for metallic as well as semiconducting single-walled NT (SWNT), [1][2][3][4][5][6][7][8] which is attributed to the electron back scattering by high energy phonon, 3 and interband zener tunneling.…”

Single Carbon Nanotube Transistor at GHz Frequency

“…Low Schottky-barrier contacts, with Pd metallisation, and quasi-ballistic transport result in a channel resistance R ds approaching the quantum limit, h/4e 2 = 6.5 kΩ for a 4-mode single walled nanotube [11]. High saturation currents, limited by optical phonon emission, allow large biases, I ds ∼ 20 µA at V ds 1 V in short nanotubes [12,13]. The above numbers and the good gate coupling explain the large transconductances, g m ∼ I ds /∆ 10 µS, observed in dc experiments [1].…”

Current-induced cleaning of graphene

“…Taking the sample width of 4 m and a thickness of 0.35 nm, this translates into an extremely large current density J of a few 10 8 A/cm 2 . For comparison, J is only a few times larger in carbon nanotubes, 11,12 and for both materials, J is several orders of magnitude larger than in present-day interconnects.…”