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rpday / chinook

Python module for simulating matrix-elements in ARPES using a tight-binding model
https://chinookpy.readthedocs.io
MIT License
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Circular dichroism calculation #7

Open Geoffroy54 opened 1 year ago

Geoffroy54 commented 1 year ago

Hi,

I am a french researcher from the Institut Jean Lamour in Nancy, France. First, I would like to thank you for the very nice work you did for the ARPES community by developping this code. It is very impressive !

I come to you because I have a question regarding the polarization vector it is possible to use in the experimental configuration : is there a simple way to perform an ARPES calculation using circularly polarized light (right/left) ? How should I define the "pol" argument in this case ?

Thank your for your help.

Best wishes, Geoffroy Kremer

rpday commented 1 year ago

Hi Geoffroy, thanks for the question. You can implement circular polarization using complex values in the pol vector.

For example, for normal-incident light, you would have [1.0,1.0j,0] and [1.0, -1.0j, 0] chinook will take care of normalization.

Note that only certain kinds of circular polarization will be captured in chinook, on account of the plane-wave final state we assume. Circular dichroism is often observed experimentally as a result of the scattering-final states which require a more sophisticated treatment like KKR. Please let me know if this helps, or if you have any other questions

Ryan

Geoffroy54 commented 1 year ago

Hi Ryan, thank you for your quick reply. I will first give a try on graphene.

Regarding the final state description : as it is mentionned in your publication, should we expect a good description at high photon energy since the scattering process are negligible, unlike the low energy regime ?

Geoffroy