0 votes
asked by (120 points)

I want to use ITensor for CTMRG, but I can't find how to do it.
Then, are there some examples of it?
I am assuming using C ++.

CTMRG(Corner Transfer Matrix Renormalization Group) is like this:

1 Answer

0 votes
answered by (70.1k points)

Hi Tatsuo,
Yes, you can definitely use ITensor to perform CTMRG calculations. However, we do not have a pre-written CTMRG code that we provide, so you would have to write it yourself.

As you know, the key steps of CTMRG are tensor contractions and singular value decompositions of certain tensors. ITensor lets you do both of these operations very conveniently.

Please let me know if you do begin writing it and need help with how to perform a certain step.

Best regards,

commented by (120 points)
Hi Miles,

Thanks a lot.

Actually, I tried to make it once, but failed.
What I do not understand well is how to deal with the indexes when I contract the tensors to expand CTM & HRTM.

When I try it again, I will explain the details of what I am in trouble.

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