conductance-gatevoltage results are in contradict with the experiment ? 4

[hzkvictory]

I dont know how to insert image(in my computer not on the net).
so I have to attach the conductance--gate voltage plot in experiments independedly.
and this is a related paper for reference: http://www.sciencedirect.com/science/article/pii/S0038109808001178


I do not know what mistake I have made in the calculation,
I guess maybe it is a rather physical problem: the conductance in experiments is conceptually different with the one in ATK?
 
hope to attract more discussion and help me solve the problem.