Hi Miles,

Thanks for your answer. I think that considering the glue tensors V is the key point to fix this problem.

I am testing the parallel DMRG for the Hubbard model with Sz, electron number, and ky conserved. Storing the wave function is very useful for the following considerations:

For challenging quasi-2D models, we usually do not know how many sweeps and states are large enough to make the result veritably converged in advance. So it is very convenient to use the stored wave function as an input when we increase the sweep numbers and bond dimensions, which avoids starting a calculation in the beginning. Therefore, that will save time and computational resources.

On the other hand, the maximum running time is limited on some public clusters, which may be one or two weeks. In addition, we need to shut down the personal cluster during power maintenance. Hence, the program will be more flexible if we can resubmit it based on the stored wave function in the previous calculation.

Bests

Zongsheng Zhou