+1 vote
asked by (200 points)

I want to know if it's possible to set two operators on the same site, like these:
ampo +="Cdagup",2,"Cdn",2; or
ampo +="Cdagup",2,"Cup",2;

I have tried these settings and got the errors:

AutoMPO: cannot put two operators on same site in a single term

So, I am wondering how to set the two operators on the same site.

Chenrong Liu

commented by (460 points)
Hi Chenrong,

I remembered using AutoMPO to make Hamiltonian with two operators on the same site myself before and it didn't cause any error, and I have seen others doing the same thing without any error on this forum, have you checked that you had the latest version of ITensor package? On the other hand, maybe you could use "Nup",2 instead of "Cdagup",2,"Cup",2 or make a new operator to represent the two operator on the same site.


commented by (200 points)
Thank you, I have solved this. I updated the package and it worked well now.

1 Answer

0 votes
answered by (70.1k points)

Thanks for the question Chenrong - it's good to keep an eye on these things and glad it's working well now.

Yixuan - thanks for the answer also. Feel free in the future to post an official answer; the forum allows multiple answers as you can see, so it's a good way for people to contribute.


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