Why the pathway from left to right and right to left is different?

[cinda]

Dear all,

I calculate the same structure for transmission pathway, but the contributions one is Left to Right, the other is Right to Left.
And the figure is quite different. Before I calculate, I think that the Right to Left is just like Left to Right but the pathway is contrary.
The fist attach figure is the transmission pathway from Left to Right, and the second attach figure is opposite. Why do they have so huge difference?

[Anders Blom]

Did you change the threshold or scaling factor for the second plot? Is there a bias applied?

[cinda]

Yes, I change threshold or scaling factor, but the figure still same situation. The value for pathway is all shown the same value. And I don't use any bias voltage.