What is the charge neutral point?

[skyhj105]

I have a question about definition of charge neutral point.
I`m reading some article about trilayer graphene, and this term, charge neutral point, is used in the article.
I googling this word, but I can`t find something which can tell me what it is.
In monolayer graphene, what i found by searching, it is equal to dirac point. But In trilayer there is no dirac point and it has some bandgap.

What is the carge neutral point in this?

 

[Greg Bernhardt]

Charge neutral point is the point at which the charge on the surface of a conductor is zero. This point is at the end of a conductor.