Real-time simulations of quantum spin chains: Density of states and reweighting approaches

@article{Buividovich2022RealtimeSO,
  title={Real-time simulations of quantum spin chains: Density of states and reweighting approaches},
  author={Pavel Buividovich and Johann Ostmeyer},
  journal={Physical Review B},
  year={2022}
}
We put the Density-of-States (DoS) approach to Monte-Carlo (MC) simulations under a stress test by applying it to a physical problem with the worst possible sign problem: the real time evolution of a non-integrable quantum spin chain. Benchmarks against numerical exact diagonalisation and stochastic reweighting are presented. Both MC methods, the DoS approach and reweighting, allow for simulations of spin chains as long as L = 40 , far beyond exact diagonalisability, though only for short… 

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Stochastic and Tensor Network simulations of the Hubbard Model

  • J. Ostmeyer
  • Physics
    Proceedings of The 39th International Symposium on Lattice Field Theory — PoS(LATTICE2022)
  • 2022
The Hubbard model is an important tool to understand the electrical properties of various materials. More specifically, on the honeycomb lattice it is used to describe graphene predicting a quantum

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