How can i model two photon absorption effect in FDTD solution?

nonlinear
plugin
tpa

#1

hi,

can anyone help me about these question?

How can i model two photon absorption effect in lumerical FDTD solution?

How can i import imaginary part of chi3 ?

How can i model two photon absorption effect in FDTD solution?


#2

It might be possible but they are considered advanced simulations and may require some effect to make your own plugin using C++. These non-linear effects need to be addressed using the plugin framework.

Imaginary part of Chi3
We have an existing Chi3 Raman Kerr model that may allow you to “set” the imaginary part of Chi3. This may not be trivial for all cases since you will need to come up with a combination of the parameters (alpha, w_raman, delta_raman, etc) to “construct” the imaginary part.

Two Photon Absorption (TPA)
It might also be possible to simulate these effects but it may require even more effort because we don’t have an exiting model in our KB yet. That said, you may find the follow thesis/reference interesting. There are some information about how other people trying to simulation these effects using an FDTD method. At the very end of this thesis (Integrated Nanoplasmonic Waveguides and Devices for All-Optical Nanocircuitry) contains some source code of a TPA plugin. The code also referenced this paper (FDTD Analysis of Two-Photon Absorption and Free-Carrier Absorption in Si High-Index-Contrast Waveguides) for the material information including other effects, such as Free Carrier Absorption (FCA), Kerr, and more.


Pump probe spectroscopy
#3

thank you for your guide.