electrode effects on resistance

[nazi]

Dear experts,

Assume that we have a linear I-V characteristic, so we can consider resistance as the slope of the I-V diagram equal to R=V/I .

Now, this resistance shows the resistance of just the scattering region? or it is the resistance of whole the device?

As the current passes through the scattering region, and the applied bias is over the scattering region, I think it should be device resistance, but I know that if we change the electrodes, the I-V curve could change which leads to a new resistance value. This shows the resistance also depends on the electrodes.

Could anyone explain this issue to me?

I really appreciate your help in advance.

Nazi

[nazi]

I think I find the answer. the resistance comes from the coupling between the electrodes and the scattering region so it depends to both contact and conductors, is it right?

[abhishek77492652]

Can you please how electrode couple with scattering region?

[nazi]

They are from same materials but the electrodes have some dopant atoms.

[Ulrik G. Vej-Hansen]

Yes, and part of the central region is always identical to the electrodes (the electrode extension region), so it is impossible to change the electrodes without also modifying the central region.