In principle, all Hamiltonians in this programm were written for 2D Systems like graphene, 2DEG-Semiconductors, etc. . However, some of these systems need more than one layer, or sheet: Think of two layers of graphene stacked on top of each other (bilayer graphene), a system containing spin (up and down component), or more complicated constructs like a topological Insulator with several bands.

Layers are supported throughout the design of Hamiltonian and Rectangle, as well as by image_Factory.