Haagerup_wave_function_overlap

Code for our paper: Operator fusion from wavefunction overlaps: Universal finite-size corrections and application to Haagerup model. Authors: Yuhan Liu, Yijian Zou, Shinsei Ryu. arXiv: 2203.14992

ED (exact diagonalization)

Created and maintained by Yuhan Liu. The code is written in python.

• Haagerup_main.py is the main function, ready to run.
  • task == 1: compute the energy-momentum spectrum
  • task == 2: compute wave function overlap
• Haagerup_ch.py contains the user-defined basis element object. The valid basis of Haagerup chain is generated iteratively, using a modified chain data structure.
• decomp_ch.py contains the function that allows for simultanesouly diagonalization.

puMPS

Created and maintained by Yijian Zou. The code is written in Julia.

• Code based on an earlier work (puMPS.jl) with Ashley Milsted and Guifre Vidal, https://github.com/FuTen/puMPS.jl
• 'SymTensor_v2.jl' contains basic operations of symmetric tensors with Abliean symmetries (currently support Z_N and U(1))
• 'sym_puMPS_v2.jl' contains puMPS algorithm using symmetric tensors. Performance in memory cost has been improved.
• 'overlap.jl' contains algorithm to compute wavefunction overlaps from puMPS and puMPS Bloch states.
• 'Haagerup_symMPO.jl' contains the MPO of the Haagerup model, both in dense tensors and symmetric tensors.
• A ready-to-run example of the code is included in the jupyter notebook. The jld files are needed to run the example.