Is it possible to do a 2D simulation in FDTD Solutions on a plane other than the default XY plane?



In FDTD solutions, if you choose the 2D solver, the solver region gets placed on the XY plane by default and there doesn’t seem to be any option to rotate it (say along the XZ or YZ plane). My question is, if I want to do a 2D simulation on the (say) XZ plane, can I do it inside FDTD Solutions?


By default, the FDTD solver only has 2D setting on the XY plane. That said, there are some ways to set up a quasi-2D simulation in a 3D FDTD solver, say on the XZ plane with the memory requirement on the scale of a 2D simulation.

The trick is make a 3D simulation region with a one-mesh-cell thick y span. Like this screenshot below:

To estimate the size of 1 mesh cell, you could first find the number of mesh points per wavelength (ppw) in the solver region. By default, for mesh accuracy 2, it is 10 ppw. In this quasi_2D_example.fsp (230.1 KB), at wavelength 1 um, material index =2, the size of a mesh cell in the material should be 1um/10ppw/2 = 0.05 um. Alternatively, increase the simulation region y span and measure the size of a mesh using the Ruler.

Similarly, users can make their own quasi-2D simulation on the YZ plane using a 3D simulation, or even a quasi-1D simulation.