Learning Forum

[tade]

hello.

I transfer the changes in carrier density caused by applied voltage from CHARGE to FDTD. Then, I use the Drude model to calculate the refractive index at various voltage levels. I revised my original paper. I am having difficulty with generating transmissions. When voltage is applied, the transmission landa does not experience any shift, even though the carrier density is being altered.

I attache the simulation file here.
What is the best way for me to deal with this situation?

[tade]

fig 3 d of the base paper:

refractive index _ landa 0V

refractive index _ landa 50V

 

[tade]

fig 4 b

refractive index to depth

[tade]

I can not attache my simulation here; then I have to take some pictures to attach here:

the link of my base paper is this:

https://www.nature.com/articles/s41598-018-20879-z

By changing the voltage, the reflectivity remains the same and there are no shifts observed.

 

[Guilin Sun]

Most likely the substrate setting is wrong: it should be large enough to penertate out PML, instead of a finite sized slab. I have seen this before:

the above setting is wrong. Below is the correct setting:

When it is a slab, it forms strong cavity which needs long simulation time. 

In addition, please visualize the np density you imported and see if the charge density changes with voltage.