Yambo Community Forum

HI,
I try to do SHG calculation in lumen, but I cannot find a forum for lumen so I ask questions here. I wonder how to set the direction for the SHG tensor chi. As far as I am concerned, Chi_ijk could be expressed as P_i=Chi_ijk E_j E_k, so how can we determine the i,j and k in lumen? I read the tutorial for lumen SHG in AlAs,
http://www.attaccalite.com/lumen/shg_in_AlAs.html and the external field is set as
ExtF_Dir
1.000000 | 1.000000 | 0.000000 |

Does it mean setting j=x and k=y? And the output for x,y,z directions should give Chi_xxy, Chi_yxy, Chi_zxy? If so, why does the tutorial plot give a label as Chi_xyz?

Dear tg825590,

I'm sorry but this is not the right place to post questions about lumen. I suggest you to contact Claudio Attaccalite, the developer, or write a post in his blog: for instance here:
https://www.attaccalite.com/lumen-code-is-online/

Finally, pleas sign your posts with your name and affiliation, this is a rule of the forum, as it is not nice to communicate with anonymous users.
Best,

Daniele

Thanks for your help! By the way how can I sign my post with name and affiliation?

wenshen

Dear Weshen,

By the way how can I sign my post with name and affiliation?

The way to do it once for all:
User control panel -> profile -> Edit signature.

Best,

Daniele