Noise properties of an individual and two crossing multiwalled carbon nanotubes

The noise properties at room temperature of multiwalled carbon nanotubes under forward bias, for frequencies between 10 Hz–10 kHz, have been investigated. The noise measurements were made for one individual multiwalled carbon nanotube (1 MW) and two crossing multiwalled carbon nanotubes (2 CMW). The excess noise found in 1 MW is consistently 1/f-like. However, 2 CMW shows higher noise level, and the noise spectrum has an unusual dependence on the current. The main origin of noise in 2 CMW was attributed to the diffusion noise.