Electric field distribution



I would like to simulate the electric field distribution from top for the attached stack. Could you please tell me how should I do this?

Thanks. Looking forward to your reply.



Hi @m.mamun,

The CHARGE solver in DEVICE won’t be able to simulate the electric field in the provided structure since metal and insulator materials form the boundaries of simulation and will not be included in the simulation. Only the electric field distribution in semiconductor materials will be reported.


Thanks for the feedback. Could you please suggest me a way to this simulation? My aim is to inject the electric field from top metal and see the electric field distribution in the active material. I would like to identify how much electric field is required ? Thanks.


Is your active material SiO2? If yes, as I mentioned you won’t be able to obtain the electric field in an insulator in DEVICE. Since the structure is quite simple, the electric field would be one-dimensional so you might wanna calculate the electric field profile analytically rather than doing a simulation. See the following link for example:



The active material is not SiO2. I missed one layer in the picture. The stack is the following:

Ag-SiO2-TiO2-Ag-Si and the active material is TiO2. So can I do the simulation of this stack with Lumerical?


If you define TiO2 as a semiconductor, and also provide the material properties for it (since we don’t have the semiconductor properties for TiO2 in our material database), you should be able to simulate the structure. See the following page on how to define a new semiconductor material in DEVICE:



First of all, can I do this simulation using FDTD and mode solutions? Or Do I have to use DEVICE to do this simulation?
Which monitor and source I should use for this simulation?

As I am a new user , I am finding it difficult to identify from where should I start.



Sorry about that. My impression was that you are looking for the electric field distribution due to electrical charge accumulation but seems like by electric field you meant light intensity distribution. If that is the case, you can use either FDTD or DEVICE DGTD. @bkhanaliloo should be able to help you in this regard. Also, if you are a new user, I’d recommend taking a online course on the solver of your choice available at Lumerical University.


Thanks for your feedback. Actually, i need electric field distribution due to electrical charge accumulation.

I will briefly explain my idea here:

I want to inject electric field to see how it affects the semiconductor material. I want to find out how much voltage I need for a certain amount of refractive index change of that semiconductor material.

So could you please now tell me which one I need to use Device or FDTD? And how should I do this simulation?



I see. You can’t inject an electric field per say but rather apply a voltage which creates an electric field across the structure. This can be done in DEVICE using the CHARGE solver. For the change in effect index, you can either use DEVICE FEEM solver or MODE or FDTD but it depends on what you are trying to do exactly. What kind of a device are you trying to simulate? Is this supposed to work as a modulator, phase shifter or anything else? Can you provide a reference (maybe a paper or article) doing a similar work so that we can have a better idea about the work you are trying to do?


Thanks for your feedback. The final device can be a MZI modulator or phase shifter . I want to simulate the attached structure with device. I did this using FDTD. But I did not know how to do this using device.

If i simulated the attached stack in DEVICE - can I view the refractive index change in the core due to voltage?
Could you please guide me how to do the simulation in DEVICE?



I’d recommend to start with the following example to get familiar with the general workflow of simulating a modulator:

However, this example is based on carrier concentration induced index perturbation not electric but is a good example to get started with modulator simulation.
Then you can have a look at the following examples which are modulators in which the index is perturbed based on electric field distribution. The main difference is the the user has to provide the model for electric field-based index perturbation as opposed to carrier density based index perturbation which the software will provide the model:

The following topics might also be useful to review:


Thanks a lot. In the first example, I need to include a FEEM solver. But I could not find the solver in DEVICE. I have attached an image of the DEVICE that I am using. Could you please tell me how to get the FEEM solver?


Are you using the latest version of DEVICE?


Yes, I am using the latest version of device.


Based on our records, the license you are using currently does not include the FEEM solver. Please ask the primary contact of the license (the person who purchased the license) to contact our sales department to see if they are eligible for adding the FEEM solver to the license.


I have talked with the primary contact. We do not have the license of FEEM solver because it was not included when they bought the license. Therefore, could you please suggest me a different way to do my simulation? Thanks, Looking forward to your feedback.


Currently, if you have a MODE license, you can get the FEEM for free. You can ask them to contact our sales department to help them with getting the license. Alternatively, if you want to run the optical simulation in MODE using the FDE solver (rather than FEEM in DEVICE) you can do the optical simulation as explained in the old version of the example (see the link below) and perform the electrical simulation based on the new version of the example.


Thanks for the feedback. I have received the FEEM license. I am currently following this tutorial-

However- I am stuck in the following sector – attached image. I could not select V in the parameter section.

As I have previously told you that my semiconductor material is TiO2. In the material section, there is a TiO2 material in the electrical and thermal database. Should I use that and I just introduce n and k in the optical material section? Do I need other properties of TiO2 for my simulation?

Thanks. Looking forward to your feedback.

Best Regards,



The reason you couldn’t select the V parameter in the sweep is that the nk import object was not loaded with charge data from CHARGE simulation. Once you load that data into the object, the parameter will appear in the object properties as shown below and then you can select it as a parameter in sweep object.

Regarding TiO2, in material database it is defined as an insulator, but if you need to define it as a semiconductor, you need to insert a new semiconductor material and put in the properties yourself. See the following link for how to create a new semiconductor: