  We report an experimental noise study of intermediate sized quasi ballistic
semiconducting multiwalled carbon nanotube (IS-MWCNT) devices. The noise is two
orders of magnitude lower than in singlewalled nanotubes (SWCNTs) and has no
length dependence within the studied range. In these channel limited devices
with small or negligible Schottky barriers the noise is shown to originate from
the intrinsic potential fluctuations of charge traps in the gate dielectric.
The gate dependence of normalized noise can be explained better using ballistic
the charge noise model rather than diffusive McWhorter model. The results
indicate that the noise properties of IS-MWCNTs are closer to SWCNTs than
thicker MWCNTs. These results can be utilized in future to analyze noise in
other purely ballistic nanoscale devices.
