graphene plasmonic switch using magnetic biasing


#1

Hi
i want to excite a graphene-plasmonic structure with magnetic biasing. my first question is, in the papers, researchers use dc magnetic field with the unit of Tesla, while the only available option is to change the amplitude of magnetic moment. how can i apply for example 2 Tesla via the amplitude of magnetic moment and number of dipoles?. the second question is to have a dc field. is it true to set the min and max frequency or wavelength of the excitation the same?. and the last question is about the orientation of magnetic dipoles. the papers state that the direction of magnetic field is in the z direction. don’t you think various orientations would be better?
my goal is to achieve the propagation and cut-off conditions by modulating the chemical potential of graphene, excited frequency and most importantly, magnitude of dc magnetic field.

impatiently waiting for your response.

Best,
Graphene-Plasmonic switch.fsp (746.0 KB)
http://aip.scitation.org/doi/pdf/10.1063/1.4769749


Add voltage to metal
#2

Hi @s_eskand,

To simulate the response of graphene in the presence of a dc magnetic field you need to modify the conductivity model. The model we have implemented does not include effects from applied dc magnetic fields. One option is to calculate the conductivity for a bunch of frequencies and the dc magnetic field you want (using expressions Eqs. 2 and 3 in the reference you mentioned). Then you can import the conductivity data using the sample 2D data material.

I also wanted to point out that the magnetic dipoles won’t generate a dc signal. They will inject a pulse with some centre frequency as a regular source in FDTD.


#3

Thanks fgomez. it was very useful


#4

Hi fgomez.
with reference to my question, i would say that i have finally found the relation between dc magnetic field and scattering rate of the graphene. so changing either the scattering rate or chemical potential results in changing the magnetic field. actually, I’m trying to observe the effect of the magnetostatic field rather than using directly of that. i think there’s no need to write the script or import the data anymore. do you agree with this?. but there’s still a major problem. with just observing the effect of the magnetostatic field, how can i excite the structure?

impatiently waiting for your response.


#5

Hi fgomez.
following your useful recommendation about importing the conductivity data using the sample 2D data material, i have trouble creating sampled 2D data materials. (for 3D materials, i have no problem). i searched the forum and found the following picture which i think it is the place i’m looking for, but i don’t know how to reach. would you please help me find it?

thanks in advance.


#6

Hi fgomez.
i am trying to regenerate an article. the graphene used in the article is an infinite sheet of graphene. would you please guide me how to define an infinite sheet of graphene?

impatiently waiting for your response.

thank you for your kind cooperation.


#7

Dear @s_eskand

As @fgomez mentioned, our model does not capture the magnetostatic effects. So, to model graphene and study it you will not need to import data which you obtained from the model.

I think you are working with conductivity (not resistivity). Also, if the model is described in units of S (independent of thickness), you will need layer thickness. Please note that when you import data, there are two options for the conductivity: S and S/m. The same discussion holds for resistivity (Ωm and Ω). Please see the screenshot below:

I hope this answered your question.


#8

Hi bkhanaliloo
thanks for your prompt reply.
i was using lumerical 2016a while the sampled 2D data is introduced in 2017a. i’m now using the latest version and there is no problem.


#9

Glad to hear that you figured it out.

Thanks