Hello, everyone! I have met a problem about the position of zero energy point in the transmission spectrum.
I tested a 1-D nanoribbon device. The nanoribbon is devided into two electrode regions and a scattering region.
Thus I think the transmission spectrum under zero bias can be totally determined by the band structure of the
nanoribbon. But the result turned out not to be what I thought....
(see figure 1)
However the shape of the transmission curve seems reasonable if I shift it upward. (see figure 2)
I guess the zero energy point in the transmission curve is a relative value.
But what's the physical meaning of the zero energy point in the transmission curve?
Is it means the fermi energy of the device ? And what's the difference between the fermi energy from the band
structure and the two probe device?