difference between I-V curves for periodic and nonperiodic central region

[waynebeibei]

Dear all,

When buliding a device configuration in a two-probe system for I-V curve, the central region can or cannot be periodic in X and Y?

For example, what is the difference between the below two configurations? The up is periodic in X without boundary, while the down is terminated by H atoms along X. The obtained I-V curves are also given, and the results are indeed distinct.

[Umberto Martinez]

looks like you already answered yourself!

the first configuration is a graphene sheet (2D periodic) and the second is a nanoribbon (1D periodic). Very different structures.

Indeed, you can have a device which is also periodic in the x and y directions.