How to increase graphene layers?


#1

Hi,
I’m trying to get absorption from 3 layers of graphene On each other on top of a special structure,I use 2D graphene rectangle to decrease simulation time.
How can I increase graphene layers with 2D rectangle not 3D rectangle?

graphene layers.fsp (288.4 KB)

Best Wishes,
Hananeh.


#2

Check those lines from the knowledge base
https://kb.lumerical.com/en/other_application_graphene_simulation_tips.html#surface_conductivity_approach
hope this helps!

In strict terms, the surface conductivity material model specified by (1)-(4) is valid only for a single graphene layer. However, under some circumstances, this model can also be used to represent multiple layers by scaling the total conductivity by the number of layers. For this purpose, a conductivity scaling factor has been included in the material parameters of the graphene material type.


#3

Thank you very much,that’s very useful.
How many layers are allowed to increase to have accurate simulation?

Best wishes,
Hananeh.


#4

Hi. The ‘conductivity scaling’ parameter in the surface conductivity model is more like a fitting parameter than a physical quantity. When you have more than one layer of graphene, you will get current flow between the layers. This cannot be modeled with the Kubo formula. However, in certain cases (e.g. Ref. [1] of graphene tunable THz metamaterial) the coupling between the layers can be insignificant and accurate results can be achieved by simply scaling the conductivity. For some structures this approach would work and for some structures it will not. You will have to check whether using this scaling factor is going to be valid for your device.