If you are looking at a materials with strong excitonic physics then yes this is true. The NLO will be not good in the low energy region. The only way to find out is to look at the approximate contribution to the NLO from excitonic effects. This you can do by calculating LO with boostrap/BSE at \omega and 2\omega and adding them together.
Such kind of work/analysis was done by J. Sipe in his old papers. You can have a look at some of the references.
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Dear Developers,
Is it possible to perform non-linear optics (NLO) calculation using the bootstrap kernel ?
If yes, how should the tasks look like ?
So far i am non successfull in telling the code to run the NLO with bootstrap kernel.
Is it possible to include the BSE kernel into NLO ?
Bests
Luca
Hi Luca,
The answer to both is no. You cannot do NLO with bootstrap or BSE.
Best
Sangeeta
Dear Sangeeta,
That would mean NLO without excitonic effects is totally unreliable.
Best
Luca
Last edit: luca 2017-04-03
If you are looking at a materials with strong excitonic physics then yes this is true. The NLO will be not good in the low energy region. The only way to find out is to look at the approximate contribution to the NLO from excitonic effects. This you can do by calculating LO with boostrap/BSE at \omega and 2\omega and adding them together.
Such kind of work/analysis was done by J. Sipe in his old papers. You can have a look at some of the references.
Ok.
Is it possible to do RT-GW-BSE for the second harmonic generation?
Last edit: luca 2017-04-03
As I said in my reply before NLO (including SHG) cannot be done with BSE.