English

Density-of-states of many-body quantum systems from tensor networks

Quantum Physics 2017-09-07 v3 Statistical Mechanics

Abstract

We present a technique to compute the microcanonical thermodynamical properties of a manybody quantum system using tensor networks. The Density Of States (DOS), and more general spectral properties, are evaluated by means of a Hubbard-Stratonovich transformation performed on top of a real-time evolution, which is carried out via numerical methods based on tensor networks. As a consequence, the free energy and thermal averages can be also calculated. We test this approach on the one-dimensional Ising and Fermi-Hubbard models. Using matrix product states, we show that the thermodynamical quantities as a function of temperature are in very good agreement with the exact results. This approach can be extended to higher-dimensional system by properly employing other types of tensor networks.

Keywords

Cite

@article{arxiv.1703.08411,
  title  = {Density-of-states of many-body quantum systems from tensor networks},
  author = {Fabian Schrodi and Pietro Silvi and Ferdinand Tschirsich and Rosario Fazio and Simone Montangero},
  journal= {arXiv preprint arXiv:1703.08411},
  year   = {2017}
}

Comments

8 pages, 7 figures