English

The problem of equilibration and the computation of correlation functions on a quantum computer

Quantum Physics 2009-10-31 v3 Condensed Matter

Abstract

We address the question of how a quantum computer can be used to simulate experiments on quantum systems in thermal equilibrium. We present two approaches for the preparation of the equilibrium state on a quantum computer. For both approaches, we show that the output state of the algorithm, after long enough time, is the desired equilibrium. We present a numerical analysis of one of these approaches for small systems. We show how equilibrium (time)-correlation functions can be efficiently estimated on a quantum computer, given a preparation of the equilibrium state. The quantum algorithms that we present are hard to simulate on a classical computer. This indicates that they could provide an exponential speedup over what can be achieved with a classical device.

Keywords

Cite

@article{arxiv.quant-ph/9810063,
  title  = {The problem of equilibration and the computation of correlation functions on a quantum computer},
  author = {Barbara M. Terhal and David P. DiVincenzo},
  journal= {arXiv preprint arXiv:quant-ph/9810063},
  year   = {2009}
}

Comments

25 pages LaTex + 8 figures; various additional comments, results and corrections

R2 v1 2026-07-22T20:04:53.959Z