Jojo, I believe that current carrying capacity in metal nanowires is proportional to cross-sectional area - before the diameter reaches the electron mean free path for the metal. But, there are other factors - length, geometry and uniformity of wire cross-section, temperature, applied voltage, cross-talk to adjacent nanowires, ... a very nonlinear relationship. (Refer to the paper I originally referenced.)
I think (but am not sure) that based on the following paper - "Room temperature ballistic conduction in carbon nanotubes" (equation 11) http://arxiv.org/ftp/cond-mat/papers/0211/0211515.pdf - that in carbon MWNTs max-current is proportional (up to mean free path) to cross-sectional area, at least at the MNWT contacts. So, I would guess the same holds for SWNTs. I find this subject awesomely complex. Probably experiment is the best way to check theory. As the great philosopher Yogi Berra allegedly said: "Theoretically, the theoretical and the empirical are the same - empirically, they're not" -- Lou Pagnucco Jojo Jaro wrote: > What you are saying is the current carrying capacity of a conductor is > proportional to the cross sectional area of the conductor. That is true > only for the macro scale. > > Current flow in a 1 dimensional SWNT appears to be governed by quite > different mechanisms. I do not believe the Current carrying capacity of a > CNT is proportional to its cross sectional area. I believe SWNTs with > smaller diameters can carry more current that MWNT with larger diameters. > I > believe that is exactly what "long coherence lengths" mean in this > context. > > Tell me where I'm wrong. > > > Jojo > > > ----- Original Message ----- > From: <[email protected]> > To: <[email protected]> > Sent: Monday, June 25, 2012 11:59 AM > Subject: Re: [Vo]:Coherent Quantum Wires and Charge Accumulation > > >> Jojo, >> Please note this correction - >> >> "...current density is directly related to radius^2..." >> - should read >> "...current is directly related to radius^2..." >> >> The extra word changes the meaning entirely. >> Too large a radius (~ electron mean free path), though, will make the >> current diffusive instead of ballistic. >> >> -- Lou Pagnucco >> >> Lou Pagnucco wrote: >>>Jojo, >>> >>>I believe in both metal nanowires and carbon SWNTs, current density is >>>directly related to radius^2 - Refer to equation(1), page 1 of - >>> >>>"Stability of Metal Nanowires at Ultrahigh Current Densities" >>>http://arxiv.org/pdf/cond-mat/0411058v3.pdf >> >> >> > > >
