Question about the mesh in "coupled" CHARGE and HEAT simulation


#1

Thanks for the example!

One question was about manually selecting the HEAT solver. It says that when “coupled” is selected for the Charge solver box in the temperature dependence instead of isothermal or non-isothermal, that CHARGE internally couples with HEAT. Does this mean that we don’t need to select the HEAT solver icon and setup the Heat solver box/mesh around the simulation area, and that is automatically done, but just not visually represented?

There is a temperature monitor inside the Charge solver heirarchy, with geometry that can be set, if HEAT icon isnt used and only CHARGE solver is present with the addition of temperature monitor, but the temperature monitor geometry(no visual box seems present) is different from the Charge solver box geometry and charge monitory geometry, does this mean that the finite element mesh for HEAT solver equation part is different than the other meshes? Or is there a final global mesh in this case that covers all the geometries?

Thanks!
XW


Application Example: Self-heating in a PIN Mach Zehnder Modulator
#2

Yes. In the “coupled” mode, you do not need to place a HEAT solver separately. The region covered by the CHARGE solver is used to solve for both electrical and heat transport.

  1. The extent of the “Temperature(CHARGE)” monitor should be shown by a yellow box like the other monitors. If you cannot see the box, one reason could be that it has the same extent of some other box (doping or solver region or generation rate or …). You may also consider upgrading your DEVICE version if you are not using the latest version. You can check for and download the latest version from here: https://www.lumerical.com/downloads/customer.html.

  2. As mentioned earlier, in “coupled” mode, both the electrical and heat transport equations are solved within the region defined by the CHARGE solver. Both these solvers therefore share the same volume and the same simulation mesh.