I am trying to explore the XXZ chain with DMRG to validate the performance of DMRG in an around the gapless phase. I would like to model systems with open boundary conditions and push the system sizes to see whether DMRG breaks down. I've got a few questions regarding this.
1. TeNPy has a built-in model for the XXZ chain at tenpy.models.xxz_chain.XXZChain, but the example for the XXZ model on the repository at https://github.com/tenpy/tenpy/blob/mai ... _length.py utilises tenpy.models.spins.SpinChain. I suspect these are equivalent?
2. I found this worksheet https://ethz.ch/content/dam/ethz/specia ... rcise9.pdf, which points to an example python script
Code: Select all
xxz_groundstate.py
3. More of a general question rather than TeNPy related, but would one expect DMRG to struggle with this problem given I am using finite systems? I've attempted to model the TFI chain similarly, and (finite) DMRG had no trouble capturing the physics around the critical point.
Thank you so much for your time!