Wrong SHG component in nl calculations

[Dean]

Dear developers,
I met a problem, i.e., the calculated second-order nonlinear susceptibility along z-direction is always zero for 2D materials with a vacuum slab along z. But, some 2D materials actually show SHG susceptibility out of plane.
I am confused about the calculated results. Is there anything I misunderstand?
Thanks in advance.

[claudio]

Dear Dr. Yimin Ding

the SHG in the non-periodic direction is not implemented in Yambo,
for this reason the output is always zero.
We plain to implement it in future version of the code

with best regards
Claudio Attaccalite

ps I updated the yambo wiki to make this point clearer

[Dean]

Dear Claudio Attaccalite,
Many thanks for your reply.
I am looking forward to the new version.
Best

[sunxl]

Dear Claudio,
Thanks for your reply.
1. I use the lastest version of the code (Yambo-5.2.0), but the output files show "Version 5.1.0 Revision 22561 Hash (prev commit) 785b4fd6f".
2. Based on your suggestion, I recombile yambo with DephMult=6. Then, set time-step to 0.01 fs and NLtime=-1 in the input, but the output is as same as previous run.(please the attachment)
3.I have make a test for hBN, and it works.
4.For my 2D system with C2v point group，it should have five non-zero SHG components, i.e., yxx,yyy, yzz, xxy,zyz. I can get SHG components including yxx,yyy,yzz, and yxy,yyz. But, according to some references, yxy and yyz should be zero, and xxy and zyz should be non-zero, which makes me confused.
Best,

Excuse me, sorry to bother you. For your material, the periodic direction component yxy should be zero, but the actual calculation result is not zero. How did you solve this problem?

Best，
sunxl

[Dean]

The problem has not been solved.

[sunxl]

Dear Dean，

Thank you very much for your answer. Wish everything goes well.

Best,
sunxl

[claudio]

Dear sunxl

may you put the DFT inputs of your system in the forum so we can test it using your system

best
Claudio