0 votes
asked by (150 points)

Hi everyone,
i don't want to use the idmrg implementation as a black box, i want to implement my self in order to understand better the method. But i haven't found any document or tensor diagrams that explain how this is implemented. I have read all the review papers and White's papers, but i need some references how this is best implemented using iTensor.

Any help will be much appreciated.

1 Answer

0 votes
answered by (70.1k points)
selected by
Best answer

Hi, so the ITensor iDMRG code is based on this paper by McCulloch:

It follows the main steps of the algorithm, but uses a different (yet equivalent) form of the growing step / ansatz for the new unit cell.

An alternative approach to infinite DMRG which you might be interested in implementing instead, since it can give much faster convergence for challenging systems, is the "VUMPS" algorithm described in this paper:

Welcome to ITensor Support Q&A, where you can ask questions and receive answers from other members of the community.

Formatting Tips:
  • To format code, indent by four spaces
  • To format inline LaTeX, surround it by @@ on both sides
  • To format LaTeX on its own line, surround it by $$ above and below
  • For LaTeX, it may be necessary to backslash-escape underscore characters to obtain proper formatting. So for example writing \sum\_i to represent a sum over i.
If you cannot register due to firewall issues (e.g. you cannot see the capcha box) please email Miles Stoudenmire to ask for an account.

To report ITensor bugs, please use the issue tracker.