In the present system, regarding calculations at higher voltages. I'm guessing my choice of higher voltage should depend on the peaks and profile in the Transmission Spectrum. For example, if I see a peak at energy 4.1 eV, I'm guessing I should I run a calculation at bias 4.1V?
As the current is calculated from -V/2 to V/2, if you see a peak at energy 4.1 eV, you should do a calculation at 8.2 V. However now comes the tricky part
and the fundemental thing about ATK compared to other transport codes - namely the self consistent response - if this was a simple transmission spectrum calculation from a bulk hamiltonian without no electric field and self-consistent feedback the 8.2 V would be correct answer - however as the molecule and ribbon near the molecule will adapt to the electric field created by the bias, it is very likely that the peak could move up or down in energy, and hence the justification of using ATK to handle/simulate these devices. That being said, If you have a transmission spectrum likes your, it is safe to assume that something dramatic is not going to happen at some low voltage, and hence that is the reason why I would use few voltage steps in the low area and many in the high area, as this is the place where the peaks might get into action and be altered.
Best regards
Nordland.
P.S There is a lot of value gained by using ATK 2008.10 for your kind of system in terms of memory and speed. I can't promise it, but I would guess for you kind of system there would be as much as factor 5 gained in speed and factor 2-4 in memory.
