English

Complexity and instability of quantum motion near a quantum phase transition

Quantum Physics 2015-06-17 v2

Abstract

We show that the number of harmonics of the Wigner function, recently proposed as a measure of quantum complexity, can be also used to characterize quantum phase transitions. The non-analytic behavior of this quantity in the neighborhood of a quantum phase transition is illustrated by means of the Dicke model and is compared to two well-known measures of the (in)stability of quantum motion, the quantum Loschmidt echo and the fidelity.

Keywords

Cite

@article{arxiv.1311.4437,
  title  = {Complexity and instability of quantum motion near a quantum phase transition},
  author = {Pinquan Qin and Wen-ge Wang and Giuliano Benenti and Giulio Casati},
  journal= {arXiv preprint arXiv:1311.4437},
  year   = {2015}
}

Comments

9 pages, 5 figures

R2 v1 2026-06-22T02:09:42.082Z