1. An overview of Renormalizer#

Renormalizer is a quantum dynamics package based on density matrix renormalization group (DMRG) and its time dependent formulation written in Python. All (TD-)DMRG algorithms are implemented within the framework of matrix product states (MPS) and matrix product operators (MPO). The package aims to provide a powerful and efficient platform for quantum dynamics simulation and method development with (TD-)DMRG. The package is still under heavy development. Please refer to our recent papers for the new developments.

1.1. How to cite#

If you use Renormalizer in your research, please cite

Bibtex entry:

@article{ren2018time,
  title={Time-dependent density matrix renormalization group algorithms for nearly exact absorption and fluorescence spectra of molecular aggregates at both zero and finite temperature},
  author={Ren, Jiajun and Shuai, Zhigang and Kin-Lic Chan, Garnet},
  journal={Journal of chemical theory and computation},
  volume={14},
  number={10},
  pages={5027--5039},
  year={2018},
  publisher={ACS Publications}
}

@article{li2020numerical,
  title={Numerical assessment for accuracy and GPU acceleration of TD-DMRG time evolution schemes},
  author={Li, Weitang and Ren, Jiajun and Shuai, Zhigang},
  journal={The Journal of Chemical Physics},
  volume={152},
  number={2},
  pages={024127},
  year={2020},
  publisher={AIP Publishing LLC}
}

If you also use the finite temperature dynamical DMRG (DDMRG) code, please cite

Bibtex entry:

@article{jiang2020finite,
  title={Finite Temperature Dynamical Density Matrix Renormalization Group for Spectroscopy in Frequency Domain},
  author={Jiang, Tong and Li, Weitang and Ren, Jiajun and Shuai, Zhigang},
  journal={The Journal of Physical Chemistry Letters},
  volume={11},
  number={10},
  pages={3761--3768},
  year={2020},
  publisher={ACS Publications}
}

1.2. Features#

  • Pure matrix product states (MPS) and matrix product operators (MPO) structure.

  • Support any Hamiltonian (operator) with an sum-of-products form.

  • Static state calculation:

    • Ground state.

    • State-averaged DMRG.

    • Excited state with Tamm-Dancoff approximation (first order MPS tangent space).

  • Wavefuntion and density matrix time-dependent propagation.

  • Real-time and imaginary-time propagation.

  • Dynamical properties in the time domain and frequency domain.

  • Support GPU acceleration.